Airbag/SRS electrical issue

Hey all

So we all like our wipers intermittent, that's fun right? How about airbags? Yeah, not so much.

I have an 09 trd sport dcsb 4x. Great truck. But this part kinda sucks, something is really up with the airbags.

They seem to get "crabby" and throw a code when someone sits in the passenger seat that is lightweight. If I have someone larger sit there, the code will clear. I think, this may be coincidence. Usually unplugging the battery for a bit will help clear it, but I did that yesterday and it didn't.

It throws a "short" code for the airbag charge on my driver side seatbelt. But I checked the module by unplugging it (with the battery unplugged. for awhile first) and my voltmeter shows no short. I had a shop look at the wiring and they said it was good. Not sure I trust them, but there you go.

So I'm wondering if there's anything else left to do, except just assume the airbag cpu is damaged and needs replacing. If it does, where is a good source to get another, and finally do I need to do anything to match that cpu to the main, or are they just plug and play? Again, of course with the battery unplugged. Thanks!

And I'm going to double check that code shortly but I think it was P130 if that makes sense. I'll edit this with the right code if it isn't, just going off memory.

 

Bumping this to try to get a Toyota techie up in here. Issue is persistent now, is there anywhere recommended to get a new airbag cpu that might take it back if I don't install it? I just want to have it on hand while I tear everything down and verify the wiring is good, even though I had a mechanic check it before. I don't trust many local mechanics around here.

 

Without having the actual code number it will be hard to diagnose, it should be B1*** , codes starting with P are powertrain codes (engine, transmission, transfer case, etc).
You can start by checking the wiring under the seats, I've seen quite a few instances where things get out of place under seats and cause airbag lights and other issues.
Sometimes connectors will get just a slight bit of corrosion in them too and cause a light, simply unplugging and plugging them back in may fix it but make sure your battery is disconnected before you start unplugging stuff related to the airbag system.

 

Yeah I meant to get that awhile ago, this is my final issue on my to do list with fixing the truck so I may have been avoiding it a little. Nervous at the possible cost on it I suppose.

Current and only active code is

B1901 Open in P/T Squib(RH) Circuit

History shows a b1660 P Seat active mode indicator, then before that another of the same b1 901. I think that active seat indicator is just a hey someone is sitting in the passenger seat.

Correct me if I am wrong - but the active code B1901 is the drivers side seat belt retention squib, right? I took that apart and checked it for an open short, volt meter (on the squib side only, not connected to the car) did not show an open short. So I'm unsure how to tell if I need that seat belt pre tensioner rebuilt, or a new airbag control module.

 

1901 is for the drivers side pretensioner 1660 is for the passenger airbag on/off indicator lights, I bet there's corrosion in a connector somewhere.
Has there ever been any water intrusion that you know of? It doesn't take much, just an ohm or 2 of resistance in the circuit can be enough to set a code.

 

No idea. It's a 10 year old truck! But I dont ford water crossings or anything. That 1660 is a new one, is that a bad code or just a history of that light going on and off? Should I get a connector cleaning kit and hit the pretensioner/clean it up?

 

I think I'd check the connector at the module itself since you have 2 unrelated codes, it's possible to have a bad module too but they rarely fail unless they get wet.

 

It's only thrown the wacky code on the pretensioner before, the other code is new. But it seems to follow that when people sit in that seat it can drop the code, system ends up happy and clears/works. I'll start checking connectors tomorrow.