2004 Sienna B0101 and B1181

[aharlan001]

Here is a head scratcher for you electrical gurus out there. I have a 04 sienna limited with 182K. I've been struggling to solve these codes but am not getting anywhere. I've tried a different airbag from a junkyard along with several different clock springs initially from a junkyard and more recently from Rock Auto. Most recently with the Rock Auto clock spring the codes went away for about a week and just came back today. I am getting B0101 and B1181. I do NOT have an airbag light lit and everything seems to function properly (horn and steering wheel buttons). Any advice?

Long story:
1. About 8 months ago I failed inspection for intermittent horn operation. I found the ground connection at the back of the horn to be a little lose so I got a junkyard airbag which did not fix the problem. I then got a junkyard clockspring and the problem went away.
2. A few months later the horn started working intermittently again. I tried another junkyard part this time from a vehicle with much lower miles. The problem went away but not long after I started getting B0101 and B1181 codes. I figured it was time to stop wasting my time with junkyard parts and went with a Rock Auto part. Threw it in and no more codes.
3. One week later the codes came back and I went back with the original airbag reinforcing the ground connection with some wire.
4. One week later codes are back again B0101 and B1181.

At this time I am at a loss. I have had terrible experience with stealerships and independent mechanics in the past. I would really like to diagnose and fix this problem myself if at all possible. The vast majority of posts on this subject point to the clock spring or airbag however this does not seem to be the problem here.... help...

 

[gnob]

I would double check all related connections for corrosion.
Consider swapping the abs ecu.
Your symptoms dont really make sense unless you have a chaffed wire or a bad connection somewhere. (or bad abs ecu)
A clock spring, especially a new one, should not fail that quick.

 

[aharlan001]

I would double check all related connections for corrosion.
Consider swapping the abs ecu.
Your symptoms dont really make sense unless you have a chaffed wire or a bad connection somewhere. (or bad abs ecu)
A clock spring, especially a new one, should not fail that quick.

I agree, I'm looking into an abs control module at the moment. I need to dig in to check the wiring that goes between the clock spring and abs ecu a little more but I'm thinking the same thing.

One thinf I'm trying to understand at the moment is it seems they used the same ecu 89170-08060 for models with and without side curtain airbags. Is there internal programming that makes them different or will a unit from a car without curtain airbags work just the same since the part number is the same?

Also upon more internet digging there were recalls for 03-04 Toyota Matrix and Avalon related to the wire harness that connects the clock spring to the ABS ECU. The recall indicated that the harness be replaced on all units and also the ecu if there were any codes.

 

[gnob]

I would have to see the ewd to answer the question properly but, i would assume that the bags all deploy simultaneously. In which case the external wiring would vary, or possibly a different ground circuit pin for curtain bags.
But typically the same number is same same.
That recall definitely looks like a good lead.

 

[aharlan001]

I would have to see the ewd to answer the question properly but, i would assume that the bags all deploy simultaneously. In which case the external wiring would vary, or possibly a different ground circuit pin for curtain bags.
But typically the same number is same same.
That recall definitely looks like a good lead.

I just traced the wires as far as possible removing the console but not the dash. No visual damage or corrosion.

I assume when you said abs ecu (and I repeated this) you meant srs (airbag) ecu which in this case toyota calls the center airbag sensor assembly?

Here is a photo of the ecu if that matters.

Also interesting the code clears itself just having the battery unplugged for a bit.

The recalls for wiring may be a lead but getting at those wires is going to be a real pain and I'm having trouble figuring out the part number for the assembly. I did check continuity for the 4 airbag wires that go from the ecu to the clockspring but they all checked out.

Lastly what I can't figure out is that this all started with the horn not working ... was this just a separate problem altogether? I can't see this being related to the ecu or ecu wiring.

 

[gnob]

The diagram i found isn't showing any connections other than the ecu and air bag on the ds. Not really showing the spiral cable other than in the horn diagram.
In which case i can't see the horn AND srs happening simultaneously and it not be a spiral cable issue.




So just to be clear here. You have stored codes but no lite. But the lite comes on at key on and goes out after start?

 

[gnob]

Moar

Toyota Sienna Service Manual: Open in Driver Side Squib Circuit - Diagnostic trouble code chart - Airbag system - Supplemental restraint system

www.tsienna.net

Toyota Sienna Service Manual: Open in Driver Side Squib 2nd Step Circuit - Diagnostic trouble code chart - Airbag system - Supplemental restraint system

www.tsienna.net

 

[gnob]

Basically if the wiring is solid, you need the ecu. Always a pita to diag. Sounds like yours comes and goes.
Pull it and open it up see if it looks funky or smells like majik smoke.

 

[aharlan001]

The diagram i found isn't showing any connections other than the ecu and air bag on the ds. Not really showing the spiral cable other than in the horn diagram.
In which case i can't see the horn AND srs happening simultaneously and it not be a spiral cable issue.



So just to be clear here. You have stored codes but no lite. But the lite comes on at key on and goes out after start?

I get codes after about a week of codes being cleared but the airbag light has never gone on outside of at startup for a few seconds then it goes off.

I am no longer having horn issues. This issue went away when the code issue started.

Seems like this must be two different issues but the chances of that are so low.

 

[aharlan001]

Moar

Toyota Sienna Service Manual: Open in Driver Side Squib Circuit - Diagnostic trouble code chart - Airbag system - Supplemental restraint system

www.tsienna.net

Toyota Sienna Service Manual: Open in Driver Side Squib 2nd Step Circuit - Diagnostic trouble code chart - Airbag system - Supplemental restraint system

www.tsienna.net

I tried the diagnostic tests measuring resistance for the spiral cable and instrument panel wire and got 0 for both. Not sure I am doing it right... anyway I ordered an airbag ecu with matching part number from a junkyard 2004 Sienna without air bag deployment and with curtain airbags. Looks like I am going to have to put 1300 miles on my 100 series carting the family cross country for Christmas after all... bummer... hopefully this fixes it

 

[aharlan001]

More thoughts.

Some say that the B0101 and B1181 codes will not go away and the ecu needs to be flashed to clear these codes. Maybe even though the cel light goes off after having the battery unplugged the codes are still there and just take time to surface? Maybe the codes are leftover from when the clockspring was bad and the horn wasn't working?

There is one report of a 1998 Tacoma needing a new airbag ecu. Hoping it's not the harness since the harness is discontinued and even if I did find one they are 3k!

 

[aharlan001]

I just discovered that the abs codes come back after clearing them quite quickly without a check engine light. I'm wondering if the engine light is actually something else and I'm not getting the code for whatever that is because I have my scanner setup to read abs codes? Next time I get the engine light I will run it for engine codes. I'm starting to think b0101 and b1181 are old codes from the clock spring that just don't go away. They cease throwing an airbag light but they are always there after having a bad clockspring...???

 

[gnob]

Glad you are coming to that conclusion. Afaik if you get a lite check at start and no lite after you should be gtg.

Ya i have noticed on my 07 the engine /abs/vsc code groupings are a ridiculous pita.
For example. I had my ex manifold out. Didn't plug in the o2 all the way. Blows code. Somehow forces a vsc code. (stupid zero calibration redo.... Again)
Another clients rav4 throwing vsc/abs when a p0420 is active.

 

[aharlan001]

Solved (I think). So the CEL came on again and I ran it for ENGINE codes this time! Sure enough I have one for P0430... I don't think the B0101 and B1181 have anything to do with the engine light. I think they are just old codes from when the clock spring was bad.