: passenger airbag sensor



justgreat
07-11-06, 12:10 PM
i just discovered on my 06 sts that once the car is started and the airbag sensor has not detected someone in the passenger seat, the sensor will not activate the airbag deployment circuitry if someone gets into the seat after the engine is started. the service manager says i'm not the first to complain about this. i started a file with customer service and i'm wondering if anyone else has this problem. it drives me crazy that i must shut the motor off to activate the airbag everytime i pick my kids up from a sporting event!!

jackg
06 sts6

Cajonkev
07-12-06, 03:09 AM
Interesting glitch that I luckily haven't come across (as yet). I do both manual and remote starts all the time before the passenger enters and have never had this one pop up.

Let us know what happens and good luck!!!

justgreat
07-12-06, 10:25 AM
i gotta get rid of the kids...i went out this morning and tried the seat after reading your post...this time with me in the passenger seat after i started the car...the circuit worked like a charm....had my son try it and the circuit didn't trigger the change to on...had him plant his butt right in the seam between the bottom cushion and the seatback...it worked!! both my daughter and son (15 and 13 years in age) weigh right around 90 pounds and apparently it's not enough mass to trigger the switch unless they're planted right over the sensor. i am so relieved that it's not a problem...for me and for cadillac...now all i have to do is run the drill with my daughter when she comes home from baby sitting.

jackg
06 sts6

ewill3rd
07-12-06, 12:40 PM
The PPS is used to monitor the pressure profile of an occupant on the front outboard passenger seat and communicate the status to the sensing and diagnostic module (SDM) whether to enable or suppress the deployment of the instrument panel (I/P) module. The PPS consists of an electronic control module and sensor mat assembly attached to the bottom seat cushion, wiring harness, and PASSENGER AIR BAG ON/OFF indicators. The PPS measures the weight of the occupant sitting in the front passenger seat as a pressure change. If the pressure from the occupant's weight is less than a specified value, the PPS module will send a suppress signal to the SDM to disable the I/P module. If the pressure from the occupant's weight is higher than a specified value, the PPS module will send an enable signal to the SDM to enable the I/P module. The PPS module will notify the customer of the enable/disable status by turning ON one of the PASSENGER AIR BAG ON/OFF indicators. The PPS monitors itself for faults and will set diagnostic trouble codes (DTCs) if a fault is detected. The PPS will also notify the SDM of a fault. The SDM will respond by requesting the instrument panel cluster (IPC) to turn the AIR BAG indicator ON.

I am pretty confident that the ignition does not need to be cycled.
I have an STS in the shop right now, I'll take a look.
I know for a fact that the PPS (passenger presence systems) on trucks will change states as people leave and enter the seat.... if they weigh enough to activate the sensor.
I am not sure what the "specified value" is but I think it's 90 pounds or something close to that.
We had a guy in my last shop that was right on the borderline (little guy) and depending on how he sat the light would turn on or off.
I'll let you know when I use my big behind to check one.

justgreat
07-12-06, 01:54 PM
the big butt test...with all the technology i had to put my ass in the seat to figure out that there wasn't a problem. actually, my daughter mentioned to me when we discovered the "problem" that she thought it might be due to the lack of weight for her and my son.

it is somewhat strange that by having her get out of the car and cycling the ignition switch, that the sensor would pick up her weight. my tests earlier were not real detailed...i couldn't come up with a definitive procedure to get the circuit to activate...it seemed as though cycling the ignition would get the sensor to detect their presense in the seat.

thanks for looking into it, i appreciate the effort.

jackg
06 sts6

ewill3rd
07-12-06, 07:07 PM
Turns out the one I had didn't have the PPS system in it so I couldn't really check. Sorry I didn't get back to you.
Glad I helped you find a way to check it.
The computer might think she's a bag of groceries or something, the PPS sensor can be picky sometimes.