Saturn sunroof motor...limit switches?
 

The sunroof in my girlfriends 2001 Saturn SC2 broke back in Aug and I
was the unlucky recipient of receiving the task of fixing it. I did a
little research and discovered that thousands of people have had the
same problem. I purchased the replacement guides from sunroof doctor,
installed them this weekend and have the module installed back in the
car.

My question is this:

Before connecting the motor back up to the unit, the thought occurred
to me that there is no evident limit switches on the sun roof
assembly. My first instinct was that there must be limit switches in
the motor that determine the start and stopping points. To test this,
I connected all the wiring back the way it was and tested the motor
(still not installed). To my surprise the motor spins endlessly when
"open" and "close" are depressed. When "vent" is depressed, the motor
will sometimes spin 2 revolutions and stop while other times it will
spin about 5 revs then stop. I find it hard to believe that this is
this complicated seeing as how many people have claimed to have
installed the replacement guides and their sunroof is working
flawlessly. I am weary of installing the motor back in the sunroof
for fear of breaking something from the motor continuing to rotate.
Any advice you can give me would be most appreciated. Thanks

-Jesse

Saturn sunroof motor...limit switches?
 

On Tue, 11 Nov 2008 08:26:15 -0800 (PST), Jstein
wrote:

The sunroof in my girlfriends 2001 Saturn SC2 broke back in Aug and I
was the unlucky recipient of receiving the task of fixing it. I did a
little research and discovered that thousands of people have had the
same problem. I purchased the replacement guides from sunroof doctor,
installed them this weekend and have the module installed back in the
car.

My question is this:

Before connecting the motor back up to the unit, the thought occurred
to me that there is no evident limit switches on the sun roof
assembly. My first instinct was that there must be limit switches in
the motor that determine the start and stopping points. To test this,
I connected all the wiring back the way it was and tested the motor
(still not installed). To my surprise the motor spins endlessly when
"open" and "close" are depressed. When "vent" is depressed, the motor
will sometimes spin 2 revolutions and stop while other times it will
spin about 5 revs then stop. I find it hard to believe that this is
this complicated seeing as how many people have claimed to have
installed the replacement guides and their sunroof is working
flawlessly. I am weary of installing the motor back in the sunroof
for fear of breaking something from the motor continuing to rotate.
Any advice you can give me would be most appreciated. Thanks

-Jesse

I don't have a wiring diagram for the vehicle, but it's possible that
power to the motor is controlled by a current sensor instead of limit
switches. The current sensor could be built into the switch or be
part of a chassis control computer.

The vent position probably isn't fixed, just wherever the sun roof
stops after a brief application of power to the motor.

The limit switches could also be magnetic reed switches that are in
the track assembly (hidden by the headliner) and are only operated
when the sun roof actually moves past them.

John

Saturn sunroof motor...limit switches?
 

In article
,
Jstein wrote:
Before connecting the motor back up to the unit, the thought occurred
to me that there is no evident limit switches on the sun roof
assembly. My first instinct was that there must be limit switches in
the motor that determine the start and stopping points.

On my car there isn't - the motor simply stalls at the end stops. If it
has auto operation it might use a current sensor to trip off the power.

--
*I don't suffer from insanity, I enjoy every minute of it *

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

Saturn sunroof motor...limit switches?
 

I'd suggest that you ask your question on the sun roof motor on the
rec.auto.makers.saturn newsgroup or check for info on the Saturn Fans Forum
at http://www.saturnfans.com/forums/

Bob


wrote in message
...
On Tue, 11 Nov 2008 08:26:15 -0800 (PST), Jstein
wrote:

The sunroof in my girlfriends 2001 Saturn SC2 broke back in Aug and I
was the unlucky recipient of receiving the task of fixing it. I did a
little research and discovered that thousands of people have had the
same problem. I purchased the replacement guides from sunroof doctor,
installed them this weekend and have the module installed back in the
car.

My question is this:

Before connecting the motor back up to the unit, the thought occurred
to me that there is no evident limit switches on the sun roof
assembly. My first instinct was that there must be limit switches in
the motor that determine the start and stopping points. To test this,
I connected all the wiring back the way it was and tested the motor
(still not installed). To my surprise the motor spins endlessly when
"open" and "close" are depressed. When "vent" is depressed, the motor
will sometimes spin 2 revolutions and stop while other times it will
spin about 5 revs then stop. I find it hard to believe that this is
this complicated seeing as how many people have claimed to have
installed the replacement guides and their sunroof is working
flawlessly. I am weary of installing the motor back in the sunroof
for fear of breaking something from the motor continuing to rotate.
Any advice you can give me would be most appreciated. Thanks

-Jesse

I don't have a wiring diagram for the vehicle, but it's possible that
power to the motor is controlled by a current sensor instead of limit
switches. The current sensor could be built into the switch or be
part of a chassis control computer.

The vent position probably isn't fixed, just wherever the sun roof
stops after a brief application of power to the motor.

The limit switches could also be magnetic reed switches that are in
the track assembly (hidden by the headliner) and are only operated
when the sun roof actually moves past them.

John