CorvetteForum - Chevrolet Corvette Forum Discussion

CorvetteForum - Chevrolet Corvette Forum Discussion (https://www.corvetteforum.com/forums/)
-   C5 Tech (https://www.corvetteforum.com/forums/c5-tech-1/)
-   -   DTC B0026 LF/Driver Frontal Deployment Loop (Single Stage or Stage 1) Open (https://www.corvetteforum.com/forums/c5-tech/1747703-dtc-b0026-lf-driver-frontal-deployment-loop-single-stage-or-stage-1-open.html)

Camaroguy22 07-03-2007 03:39 AM

DTC B0026 LF/Driver Frontal Deployment Loop (Single Stage or Stage 1) Open
 
I decided to make this problem have its own thread.

Can you guys help me fix this? My car is throwing that code. Only symptoms are the horn doesn't work if you press on it from the steering wheel...however the horn works when the alarm sounds.

Camaroguy22 07-05-2007 02:13 PM

Bump! Need Help!!!

runamuk 07-05-2007 04:12 PM

Sounds to me like the switch in the steering wheel is open, The switch is actually 2 seperate metallic strips inside the airbag cover.

I don't have my service manual in front of me but from your description thats the only thing I can think of.

BlackZ06 07-05-2007 04:47 PM

The Service Manual lists the following for DTC B0026 ....

------------------------------------------

Circuit Description

The steering wheel deployment loop consists of an inflatable restraint steering wheel module, an inflatable restraint steering wheel module coil, the steering wheel module - high control and steering wheel module - low control circuits. A shorting bar is used in the inflatable restraint steering wheel module and the inflatable restraint steering wheel module coil connectors which will short together the steering wheel module - high control and low control circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing. During a frontal crash of sufficient force the SDM will allow current to flow through the deployment loop in order to deploy the inflatable restraint steering wheel module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will store

Diagnostic Aids

Thouroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.

The following are possible causes of the malfunction:

* An open or high resistance in the steering wheel module - high or low control circuits.

* A malfunctioning steering wheel module

* A malfunctioning steering wheel module coil

* An internal SDM malfunction

ACTIONS

1) Turn OFF ignition

2) Disconnect inflatable restraint steering wheel module coil connector

3) Inspect both sides of the harness for corrosion or damaged terminals

4) If damaged

5) Replace steering wheel module coil if connector is bad, replace harness if harness side is bad.

-------------------------------

If that doesn't fix it ... the rest of the diagnostics require a J 38715-A SIR Driver/Passenger Load Tool and a Tech2 to continue diagnosis. Basically the car will need to go to the dealer at this point. Even if you could determine that, for example, the SDM needs replacing .... the new SDM has to be programmed with your VIN using a Tech2 before your restraint system will work.

Personally the SIR (airbag) system scares the s**t out of me and is about the only problem area of the car that I guarantee I will take it to a dealer for service work. I don't mess with it .... an "unintended" deployment of the airbag will at least cost money (SDM and airbags have to be replaced .... parts alone well north of $1500) and has the real potential to seriously injure you if you are near the bag when it fires. I'd recommend that you STRONGLY consider taking this one to a dealer unless you have the service manuals to help step you through the SIR system.

sks 10-17-2007 12:11 AM

do you know id there is a ground wire associated with this issue, code B0026. It is my only code and the airbag light is on. dont recall it being on before we messed with the ground wires.

BlackZ06 10-17-2007 12:07 PM

The only GND I can see for the SIR system is a BLACK/WHITE wire from the SDM to Splice Pack 208, which is then grounded at G104 with a BLACK/WHITE wire. G104 is located on the frame almost directly below the battery.

:cheers:

sks 10-17-2007 12:32 PM

Thanks. There was no airbag issue before we changed the harmonic balancer and messed with the ground wires. B0026 is my only code.

Will it cause a service engine soon light to come on?

Would pull the steering rack in changing the balancer cause this?

I think the manual says that it will disappear after 255 malfunction free iginition cycles have occurred. Perhaps the problem has been remedied and it needs to cycled more? Any other ways to ride it from the dash - reset wont work

BlackZ06 10-17-2007 12:54 PM


Originally Posted by sks (Post 1562341702)
Thanks. There was no airbag issue before we changed the harmonic balancer and messed with the ground wires. B0026 is my only code.

Will it cause a service engine soon light to come on?

Would pull the steering rack in changing the balancer cause this?

I think the manual says that it will disappear after 255 malfunction free iginition cycles have occurred. Perhaps the problem has been remedied and it needs to cycled more? Any other ways to ride it from the dash - reset wont work

The only warning a B0026 will light is the AIRBAG warning. You will not get a CHECK ENGINE indicator from it.

Ahhh .... pulled the steering rack .... did someone spin the steering wheel when it was disconnected from the steering box ???? There is a "clock spring" wire that connects the airbag to the electrical system. If the wheel turns too far, the wire will be broken, and that will set the B0026 DTC. What year is your car ????

sks 10-17-2007 08:17 PM

a 2000 6speed. Its a "Service Engine Soon" light not "Check Engine" for the record.

So the wire could tear if someone spun the steering wheel while the steering rack was off? Just confirming.

If it is the wire would it tear by the steering wheel/column?

Thanks.

runamuk 10-18-2007 08:03 AM


Originally Posted by sks (Post 1562353903)
a 2000 6speed. Its a "Service Engine Soon" light not "Check Engine" for the record.

So the wire could tear if someone spun the steering wheel while the steering rack was off? Just confirming.

If it is the wire would it tear by the steering wheel/column?

Thanks.

Are you sure the message doesn't say "service vehicle soon" ?

BTW - I think BlackZ06 is right on the money with his diagnosis, I suspect the wheel was rotated when the rack was disconnected which broke the clockspring and now the drivers side airbag is showing a dead short to ground causing the B0026 code. I did the same thing.

ajg1915 10-18-2007 09:19 AM


Originally Posted by runamuk (Post 1562359139)
Are you sure the message doesn't say "service vehicle soon" ?

BTW - I think BlackZ06 is right on the money with his diagnosis, I suspect the wheel was rotated when the rack was disconnected which broke the clockspring and now the drivers side airbag is showing a dead short to ground causing the B0026 code. I did the same thing.

:iagree: The clock spring is the yellow circular piece in the steering column. Anytime you disconnect rack you should lock wheel inside to prevent the clockspring from being broke. Also helps with steering sensor alignment.

sks 10-18-2007 12:44 PM

Yes service vehicle soon. sorry

BlackZ06 10-18-2007 06:15 PM


Originally Posted by sks (Post 1562353903)
a 2000 6speed. Its a "Service Engine Soon" light not "Check Engine" for the record.

So the wire could tear if someone spun the steering wheel while the steering rack was off? Just confirming.

If it is the wire would it tear by the steering wheel/column?

Thanks.

My parts manual shows the part number as 26069710, but when I enter that at vendor sites it comes up as invalid.

However, if you go to either ....

http://www.gmpartshouse.com

http://www.gmpartsdirect.com

And go into their on-line catalogs, you can find the part by selecting "Restraint System", then "Air Bag Componenets". then "clock spring" .... it is about an $80.00 part.

Basically think of it as a coiled wire. One end of the wire is attached to the "fixed" wiring harness, the other end is attached to the steering wheel airbag. As you turn the steering wheel the wire either coils tighter, or coils looser, depending on direction. The length of the wire is long enough to not tear at a full turn of the wheel, as the steering wheel will eventually stop when the steering rack reaches its maximum extension. However, if the steering column is detached from the steering rack, it is ossible to turn the steering wheel an unlimited number of times, and when that happens the coiled wire eventually reaches its limit and tears off its contacts.

If you have a MIL (Malfunction Indicator Light) showing on the IPC then you have another problem with the vehicle. Check for a DTC as ALMOST ALWAYS the MIL turns on when a Pxxxx DTC sets.

Be sure to disconnect the battery for AT LEAST 10 minutes before doing ANY work around the airbag system. The airbag system retains voltage so that should the battery immediately fail (disconnect) in a wreck, the airbag system has voltage to fire the bags when the SDM commands a firing.

Hope this helps (HTH)

:cheers:

sks 10-19-2007 03:49 AM

3 Attachment(s)
Again thanks for the help. This is an annoying problem. I tried to find said clockspring and couldnt. I took pictures. Can you identify it for me ?

Is it hard to replace the spring? What tools/advice do you have assuming it is broken.

Attachment 48167817

Attachment 48167818

Attachment 48167819

Plasticfan 10-19-2007 08:26 AM

BlackZ06 is is 100% correct here. The only thing I can add is your clockspring is under the steering wheel. Requires steering wheel removal to access it. It's a round yellow plastic piece about 3" in dia. Not shown in your pics. BTW, your drivers airbag is inop at this point. Be careful. HTH:)

ajg1915 10-19-2007 08:55 AM

You'll need a steering wheel puller.

Napa Auto Parts
You'll need the legs which are p/n 3510 $22.49, the puller which is p/n 2291 $19.09

Diconnect battery. Remove the center console, radio bezel and knee bolster.

In the passenger footwell remove the fuse marked for the SDM.

Under the steering wheel disconnect the yellow connectors (right side).

sks 10-19-2007 10:48 AM


Originally Posted by ajg1915 (Post 1562374706)
You'll need a steering wheel puller.

Napa Auto Parts
You'll need the legs which are p/n 3510 $22.49, the puller which is p/n 2291 $19.09

Diconnect battery. Remove the center console, radio bezel and knee bolster.

In the passenger footwell remove the fuse marked for the SDM.

Under the steering wheel disconnect the yellow connectors (right side).

Thanks so so so so much.

1) I cannot pinpoint/see that this is the exact problem until i remove the steering wheel correct?

2) How long should this take?

3) What are the "legs"?

4) B0026 will cause a "service vehicle soon light"?

BlackZ06 10-19-2007 10:51 AM


Originally Posted by sks (Post 1562375998)
Thanks so so so so much.

1) I cannot pinpoint/see that this is the exact problem until i remove the steering wheel correct?

2) How long should this take?

3) What are the "legs"?

4) B0026 will cause a "service vehicle soon light"?

1) You have to remove the steering wheel to access the airbag clockspring

2) First time - probably 3 to 4 hours

3) the "legs" grip the steering wheel - go look at a puller at an auto store and you'll understand

4) NO - I already told you above - The B0026 does NOT set the MIL. You have another problem - check for codes.

sks 10-19-2007 04:14 PM


Originally Posted by BlackZ06 (Post 1562376052)
4) NO - I already told you above - The B0026 does NOT set the MIL. You have another problem - check for codes.

Thanks. There is no other code.

BlackZ06 10-20-2007 12:22 PM


Originally Posted by sks (Post 1562380405)
Thanks. There is no other code.

The MIL is on and you have no other codes ?? What year is your car ??(you should fill out your profile). How are you displaying the codes ??? Are you ignoring History codes ??? A History code can/will set the MIL in many cases.

Use these instructions and in MANUAL mode display/list EVERY code stored in the car. I find it hard to believe that you don't have at least one or two comms codes stored in the car (Uxxxx) ....

https://www.corvetteforum.com/techti...D=26&TopicID=1


All times are GMT -4. The time now is 12:02 AM.


© 2024 MH Sub I, LLC dba Internet Brands