Question: Airbag system

[norwegianvette]

Have light in the inflatable restraint and red a bit on this in the FSM. Aparently it is a gommon problem that the grounding at one ore bothe sensors in the fraont fails. Anyone done this job before and can give me a short story in how to fix this. I am a bit worried as i dont want the bag to blow:eyerole

Regards,
Steve

 

[norwegianvette]

Location of sensors

Hi again. I cant find those sensorsad Anyone have a picture to post or some pin point location for me?

Steve

 

[norwegianvette]

Did find them.

On under the washer tank passenger side and one under battery tray driver side in case someone are looking for them. Have a yellow lead cover going to the sensors so easy to find them when you know where thay are. They looked like new and no rust at all so investegation is ongoing, any good ideas out there? SIR do not throw a code, flash 7 times when ignition is set on and new 7 flashes when engine is started and then steady light on.

Steve

 

[Hib Halverson]

Have light in the inflatable restraint and red a bit on this in the FSM. Aparently it is a gommon problem that the grounding at one ore bothe sensors in the fraont fails. Anyone done this job before and can give me a short story in how to fix this. I am a bit worried as i dont want the bag to blow:eyerole

Regards,
Steve

You say you have the Factory Service Manual so....open it up and read the parts about the location of the frame sensors up front and how to disable the SIR system before working in it.

All the info you need is in that FSM.

 

[norwegianvette]

You say you have the Factory Service Manual so....open it up and read the parts about the location of the frame sensors up front and how to disable the SIR system before working in it.

All the info you need is in that FSM.

I did and i checked the sensors. Both dry and good with no rust. My tech 1 wont read the SIR system:eyerole no codes to show and no codes to clear because of this. Light flash 7 times when ignition on and again 7 times after engine start up. Looking for a way to clear whatever codes in there but cant find a easy way, only how to read codes using jumper.

steve

 

[Hib Halverson]

It is true that the TECH 1 does not support SIR on a 90.

Flash code diagnostics by jumping certain pins on the MIL is your only choice. That's, also, the way to clear codes. All that stuff is in the FSM but I'm thinking you may not have the "Factory" Service Manual but may have an aftermarket service manual some of which are notoriously short of information. Is the book you have red, about 50-mm thick and does it say "1990 Corvette Service Manual on the cover?

If that's the book you have, see Sections 9J and 9J-A both of which cover SIR. Sec. 9J-A has all the diagnostic procedures including how to clear codes.

If the manual you have is not the Factory book, post back here and I'll try and post the instructions.

 

[Hib Halverson]

You can only clear codes at the ALDL on a 90. 91-up use a different DERM and strategy. Different DTC's too.

The OP has a 93. He needs a Tech 1 to read History codes, and to clear codes. BUT he can read active codes through the ALDL. Jumper pins A & K, the Service SIR light flashes the codes.

"DaveP85C4" is absolutely correct.
My bad.
Somehow I misread one of the posts in this thread as saying the car in question was a 90. I apologize for the mistake.

I'd say if the OP's TECH 1 will not support SIR and there are no current SIR coeds set then just keep driving the car. After a certain number of cycles the history code will clear.

 

[norwegianvette]

Code 51

Needed an adapter to read sir codes with Tech 1. Code 51 comes up and from what i understand that is an indication of a impact? Frame rails are clean and i dont have any rust on the car at all. Any good advices out there? Cleared the code but it came back when i started up.

Steve

"DaveP85C4" is absolutely correct.
My bad.
Somehow I misread one of the posts in this thread as saying the car in question was a 90. I apologize for the mistake.

I'd say if the OP's TECH 1 will not support SIR and there are no current SIR coeds set then just keep driving the car. After a certain number of cycles the history code will clear.

 

[Hib Halverson]

Needed an adapter to read sir codes with Tech 1. Code 51 comes up and from what i understand that is an indication of a impact? Frame rails are clean and i dont have any rust on the car at all. Any good advices out there? Cleared the code but it came back when i started up.

Steve

That you said you "needed" an adapter implies you now have the adapter and, with the TECH 1, you can read Code 51. Do you have the adapter? If so, when you read SIR Code 51, is it "current" or "history".

Also, when you say the Code 51 "...came back when you started up." Do you mean the SIR service light came on, again, after clearing codes and turning on the ignition, again, or that you could still see it on the TECH 1 but the SIR service light was not on?

Finally, I suggested in an earler post that you get the 93 Factory Service Manual. Do you have that book?

 

[norwegianvette]

That you said you "needed" an adapter implies you now have the adapter and, with the TECH 1, you can read Code 51. Do you have the adapter? If so, when you read SIR Code 51, is it "current" or "history".

Also, when you say the Code 51 "...came back when you started up." Do you mean the SIR service light came on, again, after clearing codes and turning on the ignition, again, or that you could still see it on the TECH 1 but the SIR service light was not on?

Finally, I suggested in an earler post that you get the 93 Factory Service Manual. Do you have that book?

Have an adapter and can read and delete codes. How do i know if its history? Only come up with 0051 on the Tech 1 screen. After clearing it i started the car and code 51 came back and the SIR light came on. I have the FSM for 1993 but have problems finding why it indicate 51 (Impact). I also have a Tech 2 which come with the same reading as i have only Chevrolet cars (3).

Regards,
Steve

 

[ecss]

Have an adapter and can read and delete codes. How do i know if its history? Only come up with 0051 on the Tech 1 screen. After clearing it i started the car and code 51 came back and the SIR light came on. I have the FSM for 1993 but have problems finding why it indicate 51 (Impact). I also have a Tech 2 which come with the same reading as i have only Chevrolet cars (3).

Regards,
Steve

The only explanation for your problem is the code is being falsely set by the DERM.
The fix is to replace the DERM.
A Current DTC 51 turns on the INFL REST indicator bulb and can be cleared by using a Tech 1.
A History DTC 51 does not turn on the INFL REST indicator bulb.

You cannot clear a History DTC 51. It's always stored in the EEprom.
I guess they did this so there is a history if the air bag was ever triggered.

The DERM will set DTC 52 when 4 DTC 51 history codes are stored.

 

[norwegianvette]

The only explanation for your problem is the code is being falsely set by the DERM.
The fix is to replace the DERM.
A Current DTC 51 turns on the INFL REST indicator bulb and can be cleared by using a Tech 1.
A History DTC 51 does not turn on the INFL REST indicator bulb.

You cannot clear a History DTC 51. It's always stored in the EEprom.
I guess they did this so there is a history if the air bag was ever triggered.

The DERM will set DTC 52 when 4 DTC 51 history codes are stored.

Thanks. I leave it as it is, to replace the Derm is a very fiddely job which i do not want to go through:eyerole Looking at the frame and everything at the front i cant see any sign of previous repairs so i guess it is a freak thing. Light came on after winter storage in my garage.
Is it possible to switch off this light or is it just a matter of removing the bulb?
Thanks again and best regards,
Steve