On Tue, 14 Nov 2006 12:19:07 +0000, The Natural Philosopher
wrote:

Derek ^ wrote:
On Sun, 12 Nov 2006 21:17:03 GMT, raden wrote:


There was someone selling a 5 series BMW for £300 in UKRM the other day
- comfy ride for 700 miles

- just go ands buy another cheap car for the trip and flog it on once
you're sorted again

I should have mentioned before it's petrol with electronic fuel
injection

It was arseing about again this morning when I went to start it.

Turning the ignition on but not as far as "start", has the "engine"
warning light flashing, and the mechanical warning light (pictogram of
a car outline with a spanner across it.) lit continuously. Turning the
key to start results in the starter turning over enthusiastically but
only sporadic firing. Buggering about like this for two/three minutes
results in the engine starting, whereupon all warning lights go out
and the car drives normally (in daylight with headlights off & minimal
electrics) .

These aren't the normal symptoms of a low battery in this car and the
starter motor does turn the engine over very well. I suppose I might
have disturbed the 12 volts feed to the electronics when I put the big
Croc clips on the battery terminals.

I had huge issues with a certain car when its battery was dying.

Yes, I could start it, but the voltage stayed permanently low..and the
electrical stuff was all over the place..ABS and transmission warning
lights stayed on for 50 miles before going out, electric windows lost
their 'home' positions..


Traded it for another car that ALSO came with a dead battery. That one
would start..but not hold charge long..and the engine was very rough
until the volts came up. A new battery under warranty fixed everything.


It seems that most of the modern electronics needs about 11v or more to
function properly, wehreas a starte will happily crank on 10 or less.

I would change the battery before dong anything else.

Resolved now, the long & short of it is the problem gradually improved
and symptoms went away one by one.

Chancing the last 700 mile return journey LeedsAberdeenLeeds in
darkness clinched it.

A work colleague suggested that I may have scrambled the memory in the
ecu and it had to "re-learn" it's settings. Only guesswork.

It's equally possible there was a bad battery connection which the
garage resolved whilst it was in for service, the rest being down to
getting some charge into it.

Thanks everybody who helped.

DG