Question on rear head rests and SRS
 

I realized that my rear head rests want to stay
in the upright position and will not fall down
when I press the headrest switch. It used to
but now it won't.
I was looking up in the factory manual for the
vacuum diagram. Any thoughts as to what is the
typical failure for this?
I also have my SRS light on and as per my home made
LED tests, it only blinks once indicating that there
is no fault but the SRS light wants to stay on.
I did replace the contact ring/brushes in the steering.
Is the non functioning of the rear head rest anything to
do with the SRS light staying on?
Or are these two separate issues?
Any suggestions would be appreciated.
Barry Shah
1990 300CE

Barry, are you sure you are in the right socket. You should be testing socket # 6. If the light is still on you should verify the circuit. I would have to look at a diagram which I don't have available, but it is my impression that the light will be on with the crash sensor unplugged. The light is turned off by the crash sensor putting batt voltage on the grounded side of the bulb (I could be wrong).

The headrests should be a separate issue.

SRS and Head Rest
 

Steve:
I mistyped that the light does stay on with the crash semsor unplugged unless I ground pin#6, then teh light goes out.
Does this make sense?
Please let me know
Thanks
Barry

No that doesn't make sense. I probably can't discuss this properly without seeing a wiring diagram but let me tell you what I think should happen.

With the crash module disconnected the MIL (malfunction indicator light - ON DASH) should be lit. With the sensor connected and the car running the light should go out if you are getting a proper code 1 (one flash when testing).

With the crash sensor unplugged the led (used for impulse testing) should be unlit UNLESS you are grounding the socket #6 at the moment.

With the sensor plugged in the led should not be lit when just plugged into the #6 socket. It should light only when the ground activation is happening or when the sensor is flashing out its answer.

Actually I think I understand your sentence: "light does stay on with the crash semsor unplugged unless I ground pin#6" now. You are talking about the inside MIL.

Read my above statements and see if they apply. If you are getting a flashing code one I would verify the above conditions and look at the MIL wiring. I suppose the sensor could still have a problem without the code being flashed but it would be very unusual.