Airbag light question

[gapost]

My daughter took her 05 Tahoe to a shop. The airbag light has been on for a while and I thought it was the sensor under the passenger seat, and they thought it might be some wiring issue under there. In any case, they told her that even though the airbag light was on, the airbag would go off in a collision. I don't think that is correct. Can anyone confirm this?

[markw8]

Everything I've ever seen and been told is, if the light is on, the system is inoperable.

 

Mark

[gmtech4]

+1000

 

 

INOPERATIVE,,

 

ABS is the same

[jwhjr]

If it is the seat position sensor, the airbag will still go off but at the rate as if the seat is all the way back. I had the driver side wire go bad for the seat postion sensor on mine and that is what I found out with my research. Below is directly from the GM SI documentation:

 

Inflatable Restraint Seat Position Sensors (SPS)

 

 

 

The seat position sensor (SPS) is used to determine the proximity of a front driver or passenger seat position with respect to the frontal air bag. The SPS interfaces with the SDM. The state of the SPS allows the SDM to disable stage 2 of the frontal air bag for a front seat that is forward of a forward/rearward point in seat track travel. The SPS is a Hall effect sensor that is mounted on the outboard seat track of both the driver and passenger seats. The seat track includes a metal bracket that shunts the SPS magnetic circuit creating 2 states of seat position. The shunted state represents a rearward seat position. The non-shunted state represents a forward position. The SPS provides 2 current ranges, one range for the shunted state and a second range for a non-shunted state. These 2 states are inputs to the SDM, state 1 (shunted) being the rearward threshold and state 2 (non-shunted) being the forward threshold. When the SDM receives input from a SPS that state 1 threshold is reached (seat is rearward) the SDM will not disable stage 2 deployment, if required by the deployment sensors. When state 2 threshold is reached (seat is forward) the SDM will disable stage 2 deployment on the side the seat is forward. The SDM monitors the SPS circuit and if a fault is detected the SDM will set codes B0083 or B0084 and defaults to disabling stage 2 frontal deployment. This will only default on the side of the vehicle the sensor has a fault. It's important to understand that the SPS is secondary to the passenger presence system (PPS) and the manual I/P module disable switch. If either one of these devices are in the disable mode, the passenger air bag will not deploy regardless of the SPS status.

[gapost]

Thanks jwhjr. That is really good information and it was probably the case. Anyhow, the shop fixed the problem. Apparently they lifted the seat and found the problem. Sorry, not sure what it was (through my daughter). But I think the code was 0083 when I checked it last.

[jwhjr]

No problem. I was also able to fix mine by replacing the wire. I just wanted to point out that an airbag light doesn't always mean that the system is inoperable.