Airbag help (solved)

WRteXan · 08-20-2012, 10:20 AM

Car is a 2005 LGT Limited with under 90k
Codes are 31 and 32, front sub sensors left and right

Not the stupid seat plug code! That's the impreza's.

I bought the car almost 2 years ago with major front end damage and the engine in the trunk. I rebuilt it and it has been fun and fast, but the airbag light has always been on. I pulled the airbag codes and they were 31 and 32. At the time of rebuild, the front sub sensors were missing, so I bought new ones (at the below mentioned dealership). I plugged them in and used the reset procedure in the FSM (grounding pin 3). That didn't work.

A while back, I took the car to the dealership and paid them for an hour just so they could plug in and read the codes. Gee, thanks. I can do that with a ground jumper and the diagnostic plug. They said that the car had been in an accident, so the front harness needed to be replaced. I asked how they made this determination, and they said that they jiggled the plugs on the sub sensors and they seemed lose.

Fast forward to this weekend. I follow the FSM procedure for checking the wiring harness to the front sub sensors. I don't have the special harnesses, so I just traced the wiring to determine what they were doing. Really, the special harnesses are just there to idiot proof the trouble shooting process. I pulled the battery, disconnected the airbags and checked the harness directly. Surprise, harness looks good. In my opinion, the plugs did not appear lose either. I'm not a subaru tech, but I'm not a newb either. I have another 2005 LGT limited that has never been in a collision, but is receiving under hood surgery at the moment. I could pull as many parts as necessary from this one for the time being, but since I had brand new sub sensors and the harness checked out good, I swapped out the control module (one of the recommended items for these codes.) Started the car and within a few seconds both codes showed up again.

My next plan is to swap the sensors from the other LGT too. But I'm worried that the code for front sub sensors may be somehow 'latched'. The manual is somewhat lacking in the true inner workings of the SRS. Is there someone who has access to / more experience with airbag diagnostic tools? I don't want to pay another $75 to read a code, I need a real diagnosis, even if it is to replace the harness. I'll know by tomorrow if swapping the sub sensors works out, but I'd like to be prepared if not. Is there a way to check the sub sensors directly? Is it kinda like checking an airbag with a multi-meter, BAD idea?

Cliff notes
Codes 31 and 32
NEW front sub sensors
swapped control module for USED one that has NEVER been in an accident
Still codes 31 and 32

Did I screw up my swapping the control module?
Is there a way to test the front sub sensors?

edit: After submitting, I realize that the special harness could possibly tell me if the connector to the front sub sensor is loose. It really didn't seem loose to me at all, but is there a way to check the connection without the special harness? i.e. check the continuity with the sub sensor in place? I just don't want to screw up the sub sensors.

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kustomautos · 08-20-2012, 10:59 AM

Well you have 3 components in you system the sensors, the module and the wiring. You have changed 2, one left to look at. Usually during a collision I seem to find pinched wiring.

atomicfire · 08-20-2012, 11:30 AM

Have you definitively checked out the harness? Leave the harness in the car, unplug both ends, and check with a multimeter?

kustomautos · 08-20-2012, 12:53 PM

Quote:

Originally Posted by atomicfire

Have you definitively checked out the harness? Leave the harness in the car, unplug both ends, and check with a multimeter?

Problem with that is a bunch of connectors have shorting bars they short both wires together when the connector is unplugged

atomicfire · 08-20-2012, 01:36 PM

Quote:

Originally Posted by kustomautos

Problem with that is a bunch of connectors have shorting bars they short both wires together when the connector is unplugged

Should make it easier to check continuity.

kustomautos · 08-20-2012, 02:17 PM

Quote:

Originally Posted by atomicfire

Should make it easier to check continuity.

True but u can't tell if the 2 wires are shorted together somewhere else

atomicfire · 08-20-2012, 02:26 PM

Quote:

Originally Posted by kustomautos

True but u can't tell if the 2 wires are shorted together somewhere else

Good point.

WRteXan · 08-20-2012, 02:59 PM

I have inspected the harness back to the firewall on both sides and it looks ok. The only wiring linked to the trouble codes is 2 wires to each front sub sensor. I disconnected the sensors and used some solid core wire inserted into the harness in the dash. Sensors disconnected, I read open across 9/20 and 15/26, the pins in connector AB6 that lead to the two sub sensors. I also read open to chassis ground. If I put a jumper at the sub sensor end, I read nearly a dead short. This is not the test procedure verbatim, but accomplishes nearly the same thing. Continuity in the wiring is good between both connectors. The insulation has not been compromised as all conductors read open to ground.

What I was more concerned about, but didn't express directly is having a used control module and exchanging the sub sensors. I'm not sure if there is any kind of calibration that needs to be done. Maybe the second control module threw the codes because it saw a different sensor. These questions aren't exactly covered in detail in the manual.

kustomautos · 08-20-2012, 03:16 PM

Dunno bout that

WRteXan · 08-20-2012, 04:13 PM

Me neither. :-(

WRteXan · 08-20-2012, 10:14 PM

GSW gave me the wrong sub sensors. I've been driving around over a year, and gave them another $75 to troubleshoot a problem they caused. I swapped the sensors from my other LGT and no code for either control module. Airbag illuminates before starting, so I know the bulb is good. The PN on the sub sensors from my other LGT (close date of mfg) is 98231AG01A. The parts sold to me are both PN 98231AG03A. Oddly enough they're slightly different physical dimensions too. Close enough that they bolt up and connect electrically, but something in the airbag control module doesn't like them.

In GSW's defense, their computer probably lists them as a new revision equivalent to the original equipment, but obviously, they're not a direct swap.

atomicfire · 08-21-2012, 02:40 PM

Glad you were able to get it sorted out. Now get the new valvebody in that 5EAT, fix the dash, and you can sell the car!

WRteXan · 08-21-2012, 07:37 PM

Nope. It's no longer for sale. That's why I started fixing it. It'll be getting a Climber D valve body in the near future. The dash is just that center piece. I'll find one on ebay for the right price... sooner or later.

08-20-2012, 10:20 AM	#1
WRteXan Scooby Specialist Member#: 223894 Join Date: Sep 2009 Chapter/Region: TXIC Location: Sugaru Land	Airbag help (solved) Car is a 2005 LGT Limited with under 90k Codes are 31 and 32, front sub sensors left and right Not the stupid seat plug code! That's the impreza's. I bought the car almost 2 years ago with major front end damage and the engine in the trunk. I rebuilt it and it has been fun and fast, but the airbag light has always been on. I pulled the airbag codes and they were 31 and 32. At the time of rebuild, the front sub sensors were missing, so I bought new ones (at the below mentioned dealership). I plugged them in and used the reset procedure in the FSM (grounding pin 3). That didn't work. A while back, I took the car to the dealership and paid them for an hour just so they could plug in and read the codes. Gee, thanks. I can do that with a ground jumper and the diagnostic plug. They said that the car had been in an accident, so the front harness needed to be replaced. I asked how they made this determination, and they said that they jiggled the plugs on the sub sensors and they seemed lose. Fast forward to this weekend. I follow the FSM procedure for checking the wiring harness to the front sub sensors. I don't have the special harnesses, so I just traced the wiring to determine what they were doing. Really, the special harnesses are just there to idiot proof the trouble shooting process. I pulled the battery, disconnected the airbags and checked the harness directly. Surprise, harness looks good. In my opinion, the plugs did not appear lose either. I'm not a subaru tech, but I'm not a newb either. I have another 2005 LGT limited that has never been in a collision, but is receiving under hood surgery at the moment. I could pull as many parts as necessary from this one for the time being, but since I had brand new sub sensors and the harness checked out good, I swapped out the control module (one of the recommended items for these codes.) Started the car and within a few seconds both codes showed up again. My next plan is to swap the sensors from the other LGT too. But I'm worried that the code for front sub sensors may be somehow 'latched'. The manual is somewhat lacking in the true inner workings of the SRS. Is there someone who has access to / more experience with airbag diagnostic tools? I don't want to pay another $75 to read a code, I need a real diagnosis, even if it is to replace the harness. I'll know by tomorrow if swapping the sub sensors works out, but I'd like to be prepared if not. Is there a way to check the sub sensors directly? Is it kinda like checking an airbag with a multi-meter, BAD idea? Cliff notes Codes 31 and 32 NEW front sub sensors swapped control module for USED one that has NEVER been in an accident Still codes 31 and 32 Did I screw up my swapping the control module? Is there a way to test the front sub sensors? edit: After submitting, I realize that the special harness could possibly tell me if the connector to the front sub sensor is loose. It really didn't seem loose to me at all, but is there a way to check the connection without the special harness? i.e. check the continuity with the sub sensor in place? I just don't want to screw up the sub sensors. * Registered users of the site do not see these ads. Last edited by WRteXan; 08-20-2012 at 10:05 PM.

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08-20-2012, 10:59 AM	#2
kustomautos Scooby Newbie Member#: 289392 Join Date: Jul 2011 Chapter/Region: TXIC Location: justin,tx Vehicle: 2000 2.5 rst 1982 brat 1978 brat	Well you have 3 components in you system the sensors, the module and the wiring. You have changed 2, one left to look at. Usually during a collision I seem to find pinched wiring.

08-20-2012, 11:30 AM	#3
atomicfire NASIOC Supporter Member#: 136296 Join Date: Dec 2006 Chapter/Region: TXIC Location: Midtown, Houston, TX Vehicle: 2005 STi OBP	Have you definitively checked out the harness? Leave the harness in the car, unplug both ends, and check with a multimeter?

08-20-2012, 02:59 PM	#8
WRteXan Scooby Specialist Member#: 223894 Join Date: Sep 2009 Chapter/Region: TXIC Location: Sugaru Land	I have inspected the harness back to the firewall on both sides and it looks ok. The only wiring linked to the trouble codes is 2 wires to each front sub sensor. I disconnected the sensors and used some solid core wire inserted into the harness in the dash. Sensors disconnected, I read open across 9/20 and 15/26, the pins in connector AB6 that lead to the two sub sensors. I also read open to chassis ground. If I put a jumper at the sub sensor end, I read nearly a dead short. This is not the test procedure verbatim, but accomplishes nearly the same thing. Continuity in the wiring is good between both connectors. The insulation has not been compromised as all conductors read open to ground. What I was more concerned about, but didn't express directly is having a used control module and exchanging the sub sensors. I'm not sure if there is any kind of calibration that needs to be done. Maybe the second control module threw the codes because it saw a different sensor. These questions aren't exactly covered in detail in the manual.

08-20-2012, 03:16 PM	#9
kustomautos Scooby Newbie Member#: 289392 Join Date: Jul 2011 Chapter/Region: TXIC Location: justin,tx Vehicle: 2000 2.5 rst 1982 brat 1978 brat	Dunno bout that

08-20-2012, 04:13 PM	#10
WRteXan Scooby Specialist Member#: 223894 Join Date: Sep 2009 Chapter/Region: TXIC Location: Sugaru Land	Me neither. :-(

08-20-2012, 10:14 PM	#11
WRteXan Scooby Specialist Member#: 223894 Join Date: Sep 2009 Chapter/Region: TXIC Location: Sugaru Land	GSW gave me the wrong sub sensors. I've been driving around over a year, and gave them another $75 to troubleshoot a problem they caused. I swapped the sensors from my other LGT and no code for either control module. Airbag illuminates before starting, so I know the bulb is good. The PN on the sub sensors from my other LGT (close date of mfg) is 98231AG01A. The parts sold to me are both PN 98231AG03A. Oddly enough they're slightly different physical dimensions too. Close enough that they bolt up and connect electrically, but something in the airbag control module doesn't like them. In GSW's defense, their computer probably lists them as a new revision equivalent to the original equipment, but obviously, they're not a direct swap.

08-21-2012, 02:40 PM	#12
atomicfire NASIOC Supporter Member#: 136296 Join Date: Dec 2006 Chapter/Region: TXIC Location: Midtown, Houston, TX Vehicle: 2005 STi OBP	Glad you were able to get it sorted out. Now get the new valvebody in that 5EAT, fix the dash, and you can sell the car!

08-21-2012, 07:37 PM	#13
WRteXan Scooby Specialist Member#: 223894 Join Date: Sep 2009 Chapter/Region: TXIC Location: Sugaru Land	Nope. It's no longer for sale. That's why I started fixing it. It'll be getting a Climber D valve body in the near future. The dash is just that center piece. I'll find one on ebay for the right price... sooner or later.