Discontinued Parts...Am i SOL?

Hey all, after several rounds of back and forth with the dealership on my airbag light they landed on a B1900 diagnosis of the driver front pretensioner harness having a short in it and the harness needs to be replaced. (both the pretensioner and ECU have been replaced) After telling me this, they proceeded to tell me that the part was discontinued and I may just be SOL.

After some looking, it seems my options are (after some home diag and maybe a second shop opinion):

1 - tear it apart and troubleshoot/repair the wire myself at home
2 - pull a wire off a junkyard truck
3 - ?

Mainly asking if anyone knows any additional possibilities? Any sources out there for discontinued parts that I might get lucky with finding a harness?

Thanks!

 

Clock spring?

 

I think I’d goto a different dealer. I wouldn’t think you’d need to resort to used parts to fix a 12 year old truck. Usually when a part is discontinued, there’s an updated replacement.

 

So from what i've gathered it's only in the pretensioner circuit, I don't know exactly how the clock spring ties into all that but I assumed that was a separate circuit or would throw a separate code? The only code it has ever given is B1900 for Driver Pretensioner Squib Circuit Short. The horn also does work, for what that's worth.

Yeah I've gotten some not so great feedback on this dealer from others, and it's backed up by my experiences, so I'm definitely leaning towards getting a second opinion on it.

 

Absolutely not true on used parts. Parts get discontinued over time, and the mfg has no requirement to make parts other than emission control stuff during the required period.

 

Sounds like they fired all the parts at it even though the problem was likely in the harness to begin with.
Airbag harness repair is generally not recommended but as long as it's a proper repair (solder and heat shrink, no butt splices or twist n tape) I wouldn't be afraid to fix it if it was mine. The hard part is probably going to be locating the short, the first place I'd look is where the wiring runs under the scuff plate between the door and the seat.

 

Harnesses aren't replaced often, and there are umpteen variations for each model, so Toyota wouldn't stock many of them.

Go to an indie shop for diagnosis, as dealers often aren't approved to do wiring repairs. A short in the harness can be verified by checking between the ECU connector and the pretensioner with a multimeter. Once the short is located, the tech can crimp in new wires.

 

Since @krm11 has an access cab, the second place I'd look is the flexible conduit at the driver's side access door hinge. According to the wiring/electrical manual, it's actually a relatively simple 2-wire circuit.

 

That is a great point, door flex wiring is always a potential place for problems.

 

That is read incorrectly, the Access Cab has the intermediate connector BF2 for SRS circuit.

 

^Thank you for the correction. Potentially faster to narrow down the problem with that connector available to split the circuit.

 

They're probably telling you the harness is n/a because they aren't sure a new one will fix it.

The little yellow connectors are notoriously easy to break if you're in a hurry. Check them carefully

Somebody needs to do some basic continuity checks along those wires - dmm set to ohms.

disconnect the wire at each end at the airbag and module so it's completely isolated, hook up the meter and see what you got. Check for continuity through the wire but also to ground to make sure it's not chafing on the frame. Flex the harness around, open/close the doors, etc.

The dealership didn't do any of that for damn sure

 

Thanks for the feedback all, the info on where to take a closer look at the harnesses is huge. I'll be tearing it apart to dig into the wiring after elk season. I've got it out to play in the snow in CO right now, airbags be damned!

 

Does anyone have the diagram of where the harness is routed around the door and what pins on the ECU match up with the pretensioner? I've got it apart and have access to both ends, just not sure which pin to check on the ECU side

 

Disconnected to the ECU, verify both wires...

 

Ok, I see now that the pretensioner goes to A22 pins 1 and 2, but there are 2x 15 pin connectors on the ECU, which is A22?

 

Thank you, and last question, do you know where the BF2 connector is? I have an access cab truck. I'm working on tracing the wire now but any direction would be super appreciated!

 

Copy, yeah I've got the seat and panels out, here's where I'm at. Blue highlighted is where I'm thinking pretensioner wires are gonna take me