Airbag light now working.

So I made a trip to a couple junk yards today.  One of the parts I picked up was a replacement circuit board for the drivers display speedometer, from a wrecked XB.  

I decided to install the board from the junk yard car, into my speedo assembly.  Here are the pictures of how it went down.


When figuring out why my airbag light wouldn't turn on , I decided to take apart the cluster to see if the light pattern was in this unit.   It is, I can see the air bag symbol next to the high beams and open door symbols on the left.

After I took apart the assembly I could see a missing LED from the circuit board. 

So I sent to the junk yard and picked up a speedo from a junked XB. 

To remove the cluster I first removed the phillips head plastic pin screw in the center of the plastic bezel. 

The bezel just pulls out.  Its is only snapped into place. 

Remove the 3 phillips screws holding the assembly in place.

Removed the one body connector.  

Tear down of the speedo assembly.

There are 4 screws in the back to remove.  Either a #1 or #2 phillips is needed.  

There are several plastic snaps around the body to un clip for the body to separate. 

Lift up this silver tang so it is straight up.  It goes through the board. 

Pull up on the black body of the ribbon cable, It does not separate just unlocks so don't pull it off. 

Pull out the ribbon cable.

There are another 4 little tangs that hood the board in place.  Pull back the tangs so the board will lift out.  

My old board with the missing LED for the airbag light. 

I pulled apart the replacement speedo in the same manner.  Here is the replacement board with ALL LED's in place. 

Assembly is the reverse order so I'm not going to show all the step but just point out a few things to remember or you will damage the board. 

Notice the 2 wide body connectors on the face of the circuit board at the bottom.  There are micro pins in the other half of the speedo the must align with these connectors.  Pay attention to them. 

When placing the board back in the body, align the micro pins and gently push the connector part of the board in place.   Also pay attention to the metal tang the goes through board and is bent over for the screw hole.  

When looking at the speedo assembly, If the pins mated with the connectors, this black bezel will still be flush.  If not, it will bulge out.  Pay attention and gentle press the pins into the connector. 

This ribbon cable is gently pressed into place and the body of the connector pushed down to lock it in. 

Bend the metal tab over .

With the board being locked into place, the micro pins mated correctly, and ribbon cable locked in and the metal tab bent in place, place the body on and begin snapping it in place. 

Add the 4 screws and snug them down.  Don't strip them. 

Put the assembly back into the car.

I tested the unit before putting the bezel in.  If there was a problem I could find it now.  My airbag light is now on.  Woohoo.

NOTICE THE MILEAGE ON THIS ODOMETER. 

This is not my vehicle mileage, my vehicle previous board had 209K miles on it.  So apparently, the memory for the milage is in the speedo circuit board assembly.  I was thinking it was in the body or vehicle ECU.   Now i have to remember that the current mileage is 35k more than my actual mileage.  

If anyone knows how to update this please let me know.  For now I'm just going to leave it. 

Tools used in this post -

Parts used in this post -
Junk yard circuit board.



 Let me know if you have any questions or would like more detail. Thanks for reading.

Why doesn't my airbag system light come on?

I noticed a while ago that my airbag system light does not illuminate.  I also noticed my horn wasn't working either.   So today was a day of investigation.

I decided to first tackle the horn issue figuring it was the easiest.   I removed the drivers airbag pad on the steering wheel using a T30 torx bit socket and discovered there was no clock spring installed.   That would also explain why my signals do not cancel either.

T30 tore bit screws on each side of steering wheel.

Missing clock spring and connectors.

This is the Spiral Cable Clock Spring I had to replace that missing from behind the steering wheel bar.

After thinking about it, I was even more curious as to why the airbag light was not coming on.  If the drives air bag was disconnected then the light should be on all the time.   The system will not turn off the light until the self check confirms all electrical components are connected and meet the resistance requirements.

After remembering back to 1995 when I was still in the dealership as a tech, I remember that the earlier instrument clusters had tiny bulbs that could be replaced if the various warning lights and indicators did not illuminate.  So I decided to remove my instrument cluster and investigate inside.

I found that the micro LED was removed from the circuit board.   ????? Why????   At some point in the life of this car, someone decided to do some modifications all over the place.  My guess is that a previous owner had an aftermarket steering wheel that did not have the airbag system, so they removed the LED to turn off the light.   There are also signs of an aftermarket stereo system installed at one point.   Extra wires area under the carpet and extra ground points are screwed into the body.

Airbag position is in the cluster, but does not illuminate.

Missing LED. 3rd position from the left .

Well I don't think I will try to fix the light itself, but I did oder a new clock spring to connect the airbag and horn again.

I later took my Snap-on Ethos scanner and plugged into my car.  I found codes for the clock spring and drivers squib open circuits in the airbag system eco.

Tools used in this post - 1/4 drive socket, 1/4 drive 3 inch extension, t30 socket. phillips #2 screwdriver.

Parts used in this post - none.

 Let me know if you have any questions or would like more detail. Thanks for reading.