Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail /
brake lamps every couple of weeks, and the same with headlamps. And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have started
shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at the
power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with the engine
running?
I'd guess around 14v.

Googling this, I have seen people saying the disco uses some fancy automatic
system to optimise the charge voltage which takes into account all sorts of
things including vehicle electrical load at the time, and temperature ( the
battery is apparently temperature sensitive ), and possibly phases of the
moon.. This can apparently cause the charge voltage to vary up to 15.5v,
I've read. ( It's -9 degrees here at the moment, and the vehicle electrics
are often well loaded with heated windows and seats, wipers, fan blowers
etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover for
a warranty claim.

Otherwise, I need to put a 7912 regulator in the DVD player power lead!

--
Ron

In article ,
"Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS writes:
Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail /
brake lamps every couple of weeks, and the same with headlamps. And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have started
shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at the
power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

That will kill the battery prematurely too.

What is reasonable maximum voltage on a vehicle 12v system with the engine
running?
I'd guess around 14v.

Googling this, I have seen people saying the disco uses some fancy automatic
system to optimise the charge voltage which takes into account all sorts of
things including vehicle electrical load at the time, and temperature ( the
battery is apparently temperature sensitive ), and possibly phases of the
moon.. This can apparently cause the charge voltage to vary up to 15.5v,
I've read. ( It's -9 degrees here at the moment, and the vehicle electrics
are often well loaded with heated windows and seats, wipers, fan blowers
etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover for
a warranty claim.

Otherwise, I need to put a 7912 regulator in the DVD player power lead!

I think you mean 7812, but you would probably need a
low dropout higher current regulator. ;-)

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS coughed up some electrons
that declared:

Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail /
brake lamps every couple of weeks, and the same with headlamps. And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have
started shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at
the power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with the engine
running?
I'd guess around 14v.

That's been my experience.

Googling this, I have seen people saying the disco uses some fancy
automatic system to optimise the charge voltage which takes into account
all sorts of things including vehicle electrical load at the time, and
temperature ( the battery is apparently temperature sensitive ), and
possibly phases of the
moon.. This can apparently cause the charge voltage to vary up to 15.5v,
I've read. ( It's -9 degrees here at the moment, and the vehicle
electrics are often well loaded with heated windows and seats, wipers, fan
blowers etc. )

15.5V seems high. 14V-14.5V would be more like the sort of voltages I've
been used to seeing with the alternator going flat out *and* the battery
fully charged *at the battery terminals* (lower at the load terminals, due
to drop in the wiring).

Thing is, 15.5V I reckon will damage the battery - and if the battery is not
fully charged, it should be holding the vehicle general supply voltage down
to something more sane**

** Meaning the alternator might produce a high-ish output voltage in order
to drive lots of amps into the battery via it's connecting leads, but the
voltage at the battery terminals shouldn't actually get that high, I
wouldn't have thought.

Am I seeing a fault ( voltage regulator on the alternator ), or is this
just within normal tollerances with these vehicles?

Do they still use "Lucas, Prince of Darkness" electrics?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

I would challenge it's operation to the dealer.

It seems too high by a good volt - my old Daewoo, I think, used one spare
bulb in it's whole time I had it (8 years) and that was the interior light.
Maybe it had a new headlamp bulb too - certainly nothing else.

Cheers

Tim

"Tim S" wrote in message
...
"Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS coughed up some
electrons
that declared:

Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm
replacing tail /
brake lamps every couple of weeks, and the same with headlamps.
And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats
have
started shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of
12v at
the power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at
around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with
the engine
running?
I'd guess around 14v.

That's been my experience.

Googling this, I have seen people saying the disco uses some fancy
automatic system to optimise the charge voltage which takes into
account
all sorts of things including vehicle electrical load at the time,
and
temperature ( the battery is apparently temperature sensitive ),
and
possibly phases of the
moon.. This can apparently cause the charge voltage to vary up
to 15.5v,
I've read. ( It's -9 degrees here at the moment, and the vehicle
electrics are often well loaded with heated windows and seats,
wipers, fan
blowers etc. )

15.5V seems high. 14V-14.5V would be more like the sort of voltages
I've
been used to seeing with the alternator going flat out *and* the
battery
fully charged *at the battery terminals* (lower at the load
terminals, due
to drop in the wiring).

Thing is, 15.5V I reckon will damage the battery - and if the
battery is not
fully charged, it should be holding the vehicle general supply
voltage down
to something more sane**

** Meaning the alternator might produce a high-ish output voltage in
order
to drive lots of amps into the battery via it's connecting leads,
but the
voltage at the battery terminals shouldn't actually get that high, I
wouldn't have thought.

Am I seeing a fault ( voltage regulator on the alternator ), or is
this
just within normal tollerances with these vehicles?

Do they still use "Lucas, Prince of Darkness" electrics?

Is it reasonable for the thing to run at 15.5v, and chew up
headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land
Rover
for a warranty claim.

I would challenge it's operation to the dealer.

It seems too high by a good volt - my old Daewoo, I think, used one
spare
bulb in it's whole time I had it (8 years) and that was the interior
light.
Maybe it had a new headlamp bulb too - certainly nothing else.

Cheers

Tim

To get more evidence, get the specifics (make / model) of the battery
and get the tech spec from the manufactures web site re max voltage
for charging. If it's being exceeded then thump Landrover !

AWEM

On Mon, 9 Feb 2009 21:40:30 -0000, Ron Lowe wrote:

I found it to be 15.6v with the engine running. IMHO, that's too high,
and possibly the cause of the lamp problem.

Agreed, stop faffing about and take it to the dealers to sort out. Report
the blowing of bulbs and the voltage you have found. It's not right, stand
your ground firmly and politely.

--
Cheers
Dave.

On Mon, 09 Feb 2009 21:40:30 +0000, Ron Lowe wrote:
Am I seeing a fault ( voltage regulator on the alternator ), or is this just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?

I wonder if something's nuked itself and you're actually getting a level
out of the alternator/regulator that's fluctuating wildly; putting a
meter on it might be showing it as an almost-stable 15-odd volts, whilst
nasty spikes are quite happily killing various bits attached to your
vehicle...

I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

The DC level you're getting definitely sounds too high - I'd expect
somewhere betwen 13V and 14V (probably toward the 14 end) for a vehicle
system.

It might be worth checking that the alternator has a good ground
connection - if that's bad due to dirt / corrosion / something working
loose then it could really mess your charging system up.

cheers

Jules

In article ,
Ron Lowe ronATlowe-famlyDOTmeDOTukSPURIOUS wrote:
I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Yes - about 14.5 max is more usual. But if the battery is fully charged,
less than that. Any time I've looked at my newest car (10 years old) it's
sitting at the classic 13.8.

--
*If I throw a stick, will you leave?

Dave Plowman London SW
To e-mail, change noise into sound.

"Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS wrote in message
...
Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail /
brake lamps every couple of weeks, and the same with headlamps. And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have
started shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at
the power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with the engine
running?
I'd guess around 14v.

Googling this, I have seen people saying the disco uses some fancy
automatic system to optimise the charge voltage which takes into account
all sorts of things including vehicle electrical load at the time, and
temperature ( the battery is apparently temperature sensitive ), and
possibly phases of the moon.. This can apparently cause the charge
voltage to vary up to 15.5v, I've read. ( It's -9 degrees here at the
moment, and the vehicle electrics are often well loaded with heated
windows and seats, wipers, fan blowers etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this
just within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

Otherwise, I need to put a 7912 regulator in the DVD player power lead!

--
Ron



You might be able to get a more definitive answer over on
uk.rec.cars.maintenance

There's some good well-savvy lads on there.

Arfa

On Feb 9, 3:40*pm, "Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS
wrote:
Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail /
brake lamps every couple of weeks, and the same with headlamps. * And at
around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have started
shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at the
power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with the engine
running?
I'd guess around 14v.

Googling this, I have seen people saying the disco uses some fancy automatic
system to optimise the charge voltage which takes into account all sorts of
things including vehicle electrical load at the time, and temperature ( the
battery is apparently temperature sensitive ), and possibly phases of the
moon.. * This can apparently cause the charge voltage to vary up to 15.5v,
I've read. * ( It's -9 degrees here at the moment, and the vehicle electrics
are often well loaded with heated windows and seats, wipers, fan blowers
etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover for
a warranty claim.

Otherwise, I need to put a 7912 regulator in the DVD player power lead!

--
Ron

15.5 has fried everything even the battery if its been in long, 13.3
-13.5 is all you should have, It shoud not be an argument.
www.batteryuniversity.com pg 13 should give you info on battery
charge. 15.5, I would not want your vehicle out of warranty.

On Mon, 09 Feb 2009 22:49:51 +0000 (GMT), "Dave Liquorice"
wrote:

On Mon, 9 Feb 2009 21:40:30 -0000, Ron Lowe wrote:

I found it to be 15.6v with the engine running. IMHO, that's too high,
and possibly the cause of the lamp problem.

Agreed, stop faffing about and take it to the dealers to sort out. Report
the blowing of bulbs and the voltage you have found. It's not right, stand
your ground firmly and politely.

Around 13·8V is the usual - that's why so-called 12V power units for
mobile CB and amateur radio are normally rated at 13·8.
I would reckon that anything much in excess of 14V needs looking at.

I suspect that LR's ethos is that Discos are likely to be fitted with
lots of accessories such as internal and rear working lights where a
higher rate of charge may seem appropriate.

--
Frank Erskine

"Jules" wrote in message
news
On Mon, 09 Feb 2009 21:40:30 +0000, Ron Lowe wrote:
Am I seeing a fault ( voltage regulator on the alternator ), or is this
just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?

I wonder if something's nuked itself and you're actually getting a level
out of the alternator/regulator that's fluctuating wildly; putting a
meter on it might be showing it as an almost-stable 15-odd volts, whilst
nasty spikes are quite happily killing various bits attached to your
vehicle...

I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

The DC level you're getting definitely sounds too high - I'd expect
somewhere betwen 13V and 14V (probably toward the 14 end) for a vehicle
system.

It might be worth checking that the alternator has a good ground
connection - if that's bad due to dirt / corrosion / something working
loose then it could really mess your charging system up.

Why would a poor earth increase the voltage of an alternator?

"Frank Erskine" wrote in message
...
On Mon, 09 Feb 2009 22:49:51 +0000 (GMT), "Dave Liquorice"
wrote:

On Mon, 9 Feb 2009 21:40:30 -0000, Ron Lowe wrote:

I found it to be 15.6v with the engine running. IMHO, that's too high,
and possibly the cause of the lamp problem.

Agreed, stop faffing about and take it to the dealers to sort out. Report
the blowing of bulbs and the voltage you have found. It's not right, stand
your ground firmly and politely.

Around 13·8V is the usual - that's why so-called 12V power units for
mobile CB and amateur radio are normally rated at 13·8.
I would reckon that anything much in excess of 14V needs looking at.

14.4 v is the normal from an alternator. 14.5 should be fine. It should
drop about a volt when the lights and demister are on. That is how you
test the alternator with a volt meter.

If you have a clamp on ammeter. When battery is dead the amps should be 0
then rise until around 20 amps once he battery starts to take the charge.
If it goes to around 10 amps or less, do the battery test.

The battery test is, charge until it is 12.2 volts. Disconnect the ign coil,
so engine does not start. Turn over the engine for 15 seconds. If the
battery dies, then it fails the test.

Dave Plowman (News) wrote:
In article ,
Ron Lowe ronATlowe-famlyDOTmeDOTukSPURIOUS wrote:
I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Yes - about 14.5 max is more usual. But if the battery is fully charged,
less than that. Any time I've looked at my newest car (10 years old) it's
sitting at the classic 13.8.

Quite, new alternator time.


NT

In article ,
"Doctor Drivel" writes:

The battery test is, charge until it is 12.2 volts. Disconnect the ign coil,
so engine does not start. Turn over the engine for 15 seconds. If the
battery dies, then it fails the test.

Make sure you've got several hundred quid spare for a new cat at the next MOT.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Mon, 09 Feb 2009 17:11:07 -0600, Jules wrote:

It might be worth checking that the alternator has a good ground
connection - if that's bad due to dirt / corrosion / something working
loose then it could really mess your charging system up.

The vehicle is still under warranty, take it back and get it fixed.

As the voltage is so high what stress is it putting on the expensive
computers than control almost everything in a D3? Getting the problem
sorted by the dealer gets it on to the vehicles records which you then
might be able to thump Land Rover with at a later date when other things
die early.

--
Cheers
Dave.

In article ,
Ron Lowe ronATlowe-famlyDOTmeDOTukSPURIOUS wrote:
Googling this, I have seen people saying the disco uses some fancy
automatic system to optimise the charge voltage which takes into
account all sorts of things including vehicle electrical load at the
time, and temperature ( the battery is apparently temperature sensitive
), and possibly phases of the moon.. This can apparently cause the
charge voltage to vary up to 15.5v, I've read. ( It's -9 degrees here
at the moment, and the vehicle electrics are often well loaded with
heated windows and seats, wipers, fan blowers etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this
just within normal tollerances with these vehicles?

Wonder if it's the Ford designed system where the engine ECU controls the
alternator? IIRC, called smart charge.

This might be some help. But just found by Googling so...

http://www.seat-skoda-service.co.uk/...t_charging.htm

--
*We waste time, so you don't have to *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Andrew Gabriel wrote:
The battery test is, charge until it is 12.2 volts. Disconnect the ign
coil, so engine does not start. Turn over the engine for 15 seconds.
If the battery dies, then it fails the test.

Make sure you've got several hundred quid spare for a new cat at the
next MOT.

And of course it's more than likely a diesel.

--
*Why is the third hand on the watch called a second hand?

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 10 Feb 2009 01:16:29 +0000, Frank Erskine wrote:

On Mon, 09 Feb 2009 22:49:51 +0000 (GMT), "Dave Liquorice"
wrote:

On Mon, 9 Feb 2009 21:40:30 -0000, Ron Lowe wrote:

I found it to be 15.6v with the engine running. IMHO, that's too high,
and possibly the cause of the lamp problem.

Agreed, stop faffing about and take it to the dealers to sort out. Report
the blowing of bulbs and the voltage you have found. It's not right, stand
your ground firmly and politely.

Around 13·8V is the usual - that's why so-called 12V power units for
mobile CB and amateur radio are normally rated at 13·8.
I would reckon that anything much in excess of 14V needs looking at.

I suspect that LR's ethos is that Discos are likely to be fitted with
lots of accessories such as internal and rear working lights where a
higher rate of charge may seem appropriate.

Many modern cars charge at a much higher voltage than the old standards -
it's part of efficiency measures I think. My car has a 120A, 14.7V
alternator (that's the nominal volatage, it will actually output higher
voltages). The alternator has three wires specifically for the engine
management to set the required output voltage (removing the plug defaults
to high output). The high voltage *will* damage normal batteries, therefore
these cars need specific battery types.

SteveW

On Tue, 10 Feb 2009 09:54:46 +0000 (GMT), Dave Plowman (News) wrote:

Wonder if it's the Ford designed system where the engine ECU controls
the alternator? IIRC, called smart charge.

Donno, but as the vehicle is also chewing through bulbs it indicates that
the entire +v rail is elevated not just the charge circuit.

--
Cheers
Dave.

In article et,
Dave Liquorice wrote:
As the voltage is so high what stress is it putting on the expensive
computers than control almost everything in a D3?

None, I'd hope. It should all be designed with overvoltage in mind. Even a
bog standard voltage regulator found in most electronics can cope with
perhaps 40 volts higher than its output continuously. And those designed
for car use are even more tolerant.

Car electronics need to be designed to cope with a *very* dirty power
source.

--
*Why is "abbreviated" such a long word?

Dave Plowman London SW
To e-mail, change noise into sound.

"Arfa Daily" wrote in message
...

"Ron Lowe" ronATlowe-famlyDOTmeDOTukSPURIOUS wrote in message
...
Hi, all.

I have a Land Rover Discovery 3 here ( still in warranty ).

The vehicle has a voracious appetite for light bulbs: I'm replacing tail
/ brake lamps every couple of weeks, and the same with headlamps. And
at around a tenner a pop for the headlamps, I'm getting a bit fed up.

Also, the kid's DVD players ( after-market ) in the back seats have
started shutting down, usually when I start the engine.

Fault-finding the DVD players, I was checking for the presence of 12v at
the power cable.

I found it to be 15.6v with the engine running.
IMHO, that's too high, and possibly the cause of the lamp problem.

Bench testing the DVD players shows that they indeed shut down at around
15.5 v ( protection, I guess. )

What is reasonable maximum voltage on a vehicle 12v system with the
engine running?
I'd guess around 14v.

Googling this, I have seen people saying the disco uses some fancy
automatic system to optimise the charge voltage which takes into account
all sorts of things including vehicle electrical load at the time, and
temperature ( the battery is apparently temperature sensitive ), and
possibly phases of the moon.. This can apparently cause the charge
voltage to vary up to 15.5v, I've read. ( It's -9 degrees here at the
moment, and the vehicle electrics are often well loaded with heated
windows and seats, wipers, fan blowers etc. )

Am I seeing a fault ( voltage regulator on the alternator ), or is this
just within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?
I don't think it is.
I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

Otherwise, I need to put a 7912 regulator in the DVD player power lead!

--
Ron



You might be able to get a more definitive answer over on
uk.rec.cars.maintenance

There's some good well-savvy lads on there.

Arfa


There's actually an interesting thread in progress regarding exactly this
question over there, right now. Seems that some modern charging systems -
notably Ford - make use of a stepped output voltage from the alternator,
controlled by the EMU. The highest output of over 15 volts seems to be as a
result of, amongst other things, outside air temperature, to compensate for
the slightly different charging requirements of a cold battery against a
warm one. Maybe the Disco uses the same or a similar system, and it's not
working correctly ?

Arfa

"Arfa Daily" gurgled happily, sounding much like
they were saying:

Seems that some modern charging systems - notably Ford
Maybe the Disco uses the same or a similar system

Since the Disco3 was engineered by Landie under Ford's ownership, it's
entirely feasible.

On Tue, 10 Feb 2009 10:52:07 +0000 (GMT), "Dave Plowman (News)"
wrote:

In article et,
Dave Liquorice wrote:
As the voltage is so high what stress is it putting on the expensive
computers than control almost everything in a D3?

None, I'd hope. It should all be designed with overvoltage in mind. Even a
bog standard voltage regulator found in most electronics can cope with
perhaps 40 volts higher than its output continuously. And those designed
for car use are even more tolerant.

Car electronics need to be designed to cope with a *very* dirty power
source.

They are indeed. "ISO 7637 load dump" in google will turn up a few
references to the transient requirements - circa 90v for half a second
iirc.


--

In article et,
Dave Liquorice wrote:
Wonder if it's the Ford designed system where the engine ECU controls
the alternator? IIRC, called smart charge.

Donno, but as the vehicle is also chewing through bulbs it indicates
that the entire +v rail is elevated not just the charge circuit.

But the alternator output is connected directly to the battery - so apart
from some voltage drop which should be tiny, the two are the same.

--
*We waste time, so you don't have to *

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

But the alternator output is connected directly to the battery - so
apart from some voltage drop which should be tiny, the two are the same.

Somehow, it wouldn't surprise me in the slightest if complex modern stuff
like this wasn't that straightforward...

Jules wrote:
On Mon, 09 Feb 2009 21:40:30 +0000, Ron Lowe wrote:
Am I seeing a fault ( voltage regulator on the alternator ), or is this just
within normal tollerances with these vehicles?

Is it reasonable for the thing to run at 15.5v, and chew up headlamps?

I wonder if something's nuked itself and you're actually getting a level
out of the alternator/regulator that's fluctuating wildly; putting a
meter on it might be showing it as an almost-stable 15-odd volts, whilst
nasty spikes are quite happily killing various bits attached to your
vehicle...

I'm looking for some opinions before I need to argue with Mr. Land Rover
for a warranty claim.

The DC level you're getting definitely sounds too high - I'd expect
somewhere betwen 13V and 14V (probably toward the 14 end) for a vehicle
system.


14.4v is genreally regarded as maximum, but 13,5 or so is 'rated'

More MAY represent a poor joint in the charging circuit

Or an our of spec regulator.


It might be worth checking that the alternator has a good ground
connection - if that's bad due to dirt / corrosion / something working
loose then it could really mess your charging system up.

cheers

Jules

Dave Plowman (News) wrote:
In article et,
Dave Liquorice wrote:
Wonder if it's the Ford designed system where the engine ECU controls
the alternator? IIRC, called smart charge.

Donno, but as the vehicle is also chewing through bulbs it indicates
that the entire +v rail is elevated not just the charge circuit.

But the alternator output is connected directly to the battery - so apart
from some voltage drop which should be tiny, the two are the same.

*Should be* is the operative phrase here.

On Tue, 10 Feb 2009 02:08:47 +0000, Doctor Drivel wrote:
Why would a poor earth increase the voltage of an alternator?

I believe it messes up the voltage regulation if anything in the charge
circuit goes high-resistance, such that the regulators end up putting out
a higher voltage than they should.

Jules wrote:
On Tue, 10 Feb 2009 02:08:47 +0000, Doctor Drivel wrote:
Why would a poor earth increase the voltage of an alternator?

I believe it messes up the voltage regulation if anything in the charge
circuit goes high-resistance, such that the regulators end up putting out
a higher voltage than they should.


Check on the battery type. If it is the Ford smart charge system then
the battery should be a silver cadmium battery and will charge at 15 or
more volts. The voltage is not only a function of the the smart charge
controller but also of ambient temperature.
I have this system on my Cmax and it was the subject of a recall where
the batteries were becoming discharged in cold weather and failing to
start especially the diesels.
If the OP has this system then it is vital that any replacement
batteries are of the silver cadmium type.
Another characteristic of the Smart Charge system is the delay in
reacting to a heavy load on the battery.
I notice that the heater blower gets considerably louder/faster tens of
seconds after pulling away with heavy loads such as lights and heated
front screen switched on.
On my other older car, the fan speeds up instantly after pulling away.

Blowing bulbs is obviously unacceptable so the vehicle should still be
checked under warranty.

Bob

On Tue, 10 Feb 2009 14:20:53 +0000 (GMT), Dave Plowman (News) wrote:

Donno, but as the vehicle is also chewing through bulbs it indicates
that the entire +v rail is elevated not just the charge circuit.

But the alternator output is connected directly to the battery - so
apart from some voltage drop which should be tiny, the two are the same.

Assuming that there isn't some form of regulator between the battery and
the car +v rail. What happens in a car with one of these "over voltage"
charging systems? Surely the whole vehicle +v rail doesn't also rise or
you end up chewing bulbs... There is more to this over voltage charging
system than meets the eye.

--
Cheers
Dave.

On Tue, 10 Feb 2009 14:35:39 +0000, Adrian wrote:

"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

But the alternator output is connected directly to the battery - so
apart from some voltage drop which should be tiny, the two are the same.

Somehow, it wouldn't surprise me in the slightest if complex modern stuff
like this wasn't that straightforward...

Yeah, I've never quite understood the philosophy behind taking a utility
vehicle and loading it up to the gills with technology :-)

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Steve Walker
saying something like:

Many modern cars charge at a much higher voltage than the old standards -
it's part of efficiency measures I think. My car has a 120A, 14.7V
alternator (that's the nominal volatage, it will actually output higher
voltages). The alternator has three wires specifically for the engine
management to set the required output voltage (removing the plug defaults
to high output). The high voltage *will* damage normal batteries, therefore
these cars need specific battery types.

Sounds like a right load of ********.

In article ,
Grimly Curmudgeon wrote:
Many modern cars charge at a much higher voltage than the old standards
- it's part of efficiency measures I think. My car has a 120A, 14.7V
alternator (that's the nominal volatage, it will actually output higher
voltages). The alternator has three wires specifically for the engine
management to set the required output voltage (removing the plug
defaults to high output). The high voltage *will* damage normal
batteries, therefore these cars need specific battery types.

Sounds like a right load of ********.

Think there is something in it - but all good quality batteries are
calcium types these days anyway.

--
*Always remember you're unique, just like everyone else.

Dave Plowman London SW
To e-mail, change noise into sound.

On Tue, 10 Feb 2009 16:12:52 -0600, Jules
wrote:

On Tue, 10 Feb 2009 14:35:39 +0000, Adrian wrote:

"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

But the alternator output is connected directly to the battery - so
apart from some voltage drop which should be tiny, the two are the same.

Somehow, it wouldn't surprise me in the slightest if complex modern stuff
like this wasn't that straightforward...

Yeah, I've never quite understood the philosophy behind taking a utility
vehicle and loading it up to the gills with technology :-)

Simply because the type of person who buys such a vehicle tends to be
the type who falls for all this type of hype, and probably uses
oxygen-free copper 'cables' for their hi-fi type stuff...

--
Frank Erskine

Frank Erskine wrote:
On Tue, 10 Feb 2009 16:12:52 -0600, Jules
wrote:

On Tue, 10 Feb 2009 14:35:39 +0000, Adrian wrote:

"Dave Plowman (News)" gurgled happily, sounding
much like they were saying:

But the alternator output is connected directly to the battery - so
apart from some voltage drop which should be tiny, the two are the same.
Somehow, it wouldn't surprise me in the slightest if complex modern stuff
like this wasn't that straightforward...
Yeah, I've never quite understood the philosophy behind taking a utility
vehicle and loading it up to the gills with technology :-)

Simply because the type of person who buys such a vehicle tends to be
the type who falls for all this type of hype, and probably uses
oxygen-free copper 'cables' for their hi-fi type stuff...

Total rubbbish. At least round here.

Disco is the car of choice for someone who needs off road, and also
needs a practical comfortable motorway car as well.

Defender is better off road, but its noisy and uncomfortable.

People who tow horseboxes or sailing dinghys, or indeed any sport that
requires you to go on poor surfaces with load.

And yet its stillsmart enouigh to go 'to town' in in a suit..

On Wed, 11 Feb 2009 05:37:16 +0000, The Natural Philosopher wrote:
Simply because the type of person who buys such a vehicle tends to be
the type who falls for all this type of hype, and probably uses
oxygen-free copper 'cables' for their hi-fi type stuff...

Total rubbbish. At least round here.

Yeah, I think that's maybe a bit harsh, but...

Disco is the car of choice for someone who needs off road, and also
needs a practical comfortable motorway car as well.

Well, our truck's practical and comfortable, and it's over 40 years old*.
I have no problem with those aims - I just don't follow the logic of
over-complicating fundamental vehicle systems (or things like loading it
up with trim that's just going to add weight and get scuffed/wrecked)

* although only 2wd right now until I find a 4wd donor - it's on the to-do
list...

Defender is better off road, but its noisy and uncomfortable.

Hmm, noise is a good one... although every "larger than car-size" vehicle
I've been in has seemed noisy, modern or otherwise, so I'm not sure I'd
appreciate attempts to make it just a little bit quieter.

And yet its stillsmart enouigh to go 'to town' in in a suit..

I suppose you have expensive tax and MOTs over there (and less space on
average), so it's harder to run several vehicles and just use the most
appropriate one for a job

cheers

J.

In article . com,
Jules wrote:
Disco is the car of choice for someone who needs off road, and also
needs a practical comfortable motorway car as well.

Well, our truck's practical and comfortable, and it's over 40 years old*.
I have no problem with those aims - I just don't follow the logic of
over-complicating fundamental vehicle systems (or things like loading it
up with trim that's just going to add weight and get scuffed/wrecked)

I don't really see that controlling the alternator output by the engine
ECU is over complicating things. Actually makes a deal of sense. The ECU
already controls idle speed and the two are interrelated. Means it can
also reduce the output when full power is called for.

--
*I'd kill for a Nobel Peace Prize *

Dave Plowman London SW
To e-mail, change noise into sound.

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Dave Plowman (News)"
saying something like:

Sounds like a right load of ********.

Think there is something in it - but all good quality batteries are
calcium types these days anyway.

The problem then is the need to keep a calcium battery properly up
without substantially shortening the lives of the vehicle lamps. There
would be very little leeway in it and the slightest wander of the
voltage control would be popping bulbs - which is what seems to be
happening. So much for progress.
Of course, every lighting circuit could be individually or collectively
voltage protected, but that would add a significant cost.

"Frank Erskine" wrote in message
...

Simply because the type of person who buys such a vehicle tends to be
the type who falls for all this type of hype, and probably uses
oxygen-free copper 'cables' for their hi-fi type stuff...

Well, I'm not guilty of oxygen-free cables.
I do, however, have 3 runs of high quality cable from my tri-anps to my Linn
Isobariks.
Does that count ? :-)

As to the choice of vehicles:

I live near Aberdeen, and commute to Montrose daily, over either the
Netherly road or the Slug road. These can become difficult sometimes in
winter. With the disco, it's a much more pleasant experience than with my
old Audi A4.

We are members of the Gordon Skiers ( http://www.gordonskiers.co.uk/ ) ,
which requires us to be at the Lecht ski centre for 09:00 on a Sunday
morning. I routinely cart 5 or 6 kids to the lecht, or Glenshee, along
with all their ski gear for race training. The disco is absolutely the
tool for this. Sunday mornings at the snow gate at Cock Bridge at 8:30,
there's a queue of a dozen discos and other 4wd, mostly from the club,
waiting for the snow blower to clear a good enough path for the gates to
open. Last Sunday, we ended up at Glenshee, but a bit late. The car park
was full, and Plod was patrolling up and down making sure no-one parked on
the road. I was able to go into the 'full' car-park, and drive up a fairly
off-road snowfield at the enge of the car-park, and park there ( as had
other discos etc ). At the end of the day, I towed 2 stuck
rear-wheel-drive BMWs out of the car park :-) Fantastic conditions, BTW.

Summer brings sailing, and I'm towing lasers and dart catamarans around the
place.
Disco is again the tool of choice.

Motorway blast down to in-laws in Shropshire, the disco is an impeccable
motorway cruiser.

Given the mix of uses I have, I can't think of any single vehicle that would
suit me better.

--
Ron

On Wed, 11 Feb 2009 17:30:18 +0000, Grimly Curmudgeon wrote:

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember "Dave Plowman (News)"
saying something like:

Sounds like a right load of ********.

Think there is something in it - but all good quality batteries are
calcium types these days anyway.

The problem then is the need to keep a calcium battery properly up
without substantially shortening the lives of the vehicle lamps. There
would be very little leeway in it and the slightest wander of the
voltage control would be popping bulbs - which is what seems to be
happening. So much for progress.
Of course, every lighting circuit could be individually or collectively
voltage protected, but that would add a significant cost.

There were certainly plans to utilise a 36V system (although it was to be
referred to as a 42V system), the higher voltage meaning lower losses for
the high power consumers, allowing thinner (lighter) wiring, smaller motors
and powerful, fast starters - permitting engines to be shut off when
stationary. 36V is as high as they could go while keeping peak voltages on
the ac side to around the 50V considered safe for dc systems that people
may come into contact with. This would of course require various voltages
for different systems, but was considered to provide a useful fuel saving.
Apparently the idea was killed off by the difficulties of switching higher
dc voltages without erosion of the switch contacts and by the prospect of
much higher voltage hybrids with inverters and ac drives.

SteveW