09-09-11, 09:29 PM
Hi everyone. I have a 2005 STS V8 that recently started having an issue with the drivers lumbar. Each time I enter the car and or when the car is first started, the lumbar motor will start running and in doing so, makes a loud clacking type noise. The noise will stop if I depress the lumber seat switch. It will also stop making the noise after about 15sec. if I do not depress the switch. I have tried to deflate the lumbar, but it seems it will only move up and down, but not deflate or inflate more. Any suggestions as to what may be the problem would be appreciated. Is this a diy type of repair?
09-10-11, 12:56 AM
My first guess is that the lumbar has reached its limit, but the sensor isn't working and doesn't detect this. I believe the controller continues to operate the motor while monitoring the sensor and waiting for the correct input. This of course doesn't happen and times out or stops with manual input (which also makes sense based on how the system works). This might be tricky, depending on your technical ability.
09-10-11, 04:34 PM
Thanks for the information. Sounds logical to me. Where is the sensor? I made a brief attempt to remove the back seat panel, but using my finger tips, it did not want to come loose. Does that panel just snap in place or is it attached some other way? Thanks again.
09-10-11, 05:45 PM
As I recall, the seat back has tabs at the top that slide into grooves. You must first pull the seat back panel away at the bottom to release a couple of clips, it will then slide down and out to complete panel removal. Mine was pretty easy. I think there's also a flap across the bottom held in place by velcro you might need to pull this away as the first step.
Once you're in there, try and locate the lumbar position sensors, there should be two of them. One will be for up/down and the other for in/out. When I first got my car, I had a DTC set for a lumbar horizontal position fault. I unplugged the sensor, plugged it back in and everything has been fine since. In my case the connector just needed to be reseated.
09-16-11, 09:30 AM
If you have the memory seat function you can disable it and the seat will not move when you first start the car. This is temporary until you fix it or keep it at a set position and leave it there.
I rarely adjust the lumbar support. So I set the exit position of the seat the same as the driving position, then I move the seat back and set the exit position. This way the only motor that works is the motor that pulls the seat to the back to leave more room for me to exit.