xcalderon

2009 RX350, SRS light came on. Code reads: B1100 Center Airbag Sensor Assembly Malfunction
Read more: https://www.autocodes.com/b1100_toyota.html

I tried resetting the code but the light comes back on. I tried removing both battery terminals for a day and still comes on.
Would anyone know what could I do other than taking it to the Lexus Dealer? Thanks in advance.

Nad1370

I wouldnt even try anything other than what you just did.
Either the Center airbag sensor assembly is bad or issues with the SRS harness.
Have an able shop take a look at it.
Did an accident occur prior to the SRS light coming on?

xcalderon

I purchased the car last week with the light ON from a friend. IDK if it was in minor accident where airbags were not deployed but she assured me NO. Very slight possibility it may have been; or some sort of bump/shake perhaps. Since the Harness or connection may be suspect of cause, I began removing the center console, of course, with the battery cables off at all times; to reach the module and inspect wiring and harness. Sometimes plugging out and in makes a good seat or dialectric grease helps. Sometimes you may find a pinched wire or mice rot. Who knows, is an 09. Other than that, that is my very last stop; I think. Also to consider, for $50 I could send to MyAirbags.com or other service to be initialized but they claim only if it was in an accident that would help; still cheap to try.

The challenge I have now is how to remove the lower portion of the center console. I removed the shifter trim and the CIG lighter plate, however, the lower portion is pretty tough.

Any ideas or suggestions would be kindly appreciated.

Nad1370

Lower center panel is held with screws.
Some are hidden behind the lower panel on the driver side and glove box.
So both of those need to come off to access the screws. (one screw on each side i believe)

I'll advise not to use any type of grease esp on SRS connectors.
Just my opinion though.

Margate330

Those connectors and squibs on the SRS/ABS components don't fall off easy so I guess anything is possible.

>> I suspect there could possibly be more to this picture than what the previous owner said(I hope not).

Did you scan with a dealer level scanner like Techstream to see all possible codes?
If not reccomend taking to dealer too.

PS- I have noticed that some scanners that claim to do ABS/SRS will only pick up some of the codes but a dealer level scanner will find them all.

xcalderon

Nad1370: Thanks for the tips on the lower panel, will look into it.
Dialectric grease is formulated for electrical connectors but you made me think here. hmmm... better be safe than sorry. Also, ACF-50 is very good for electrical connections; FYI.
But your warning is not to be taken lightly; SRS is something to be taken seriously and with respect. Thanks.

xcalderon

Margate330: What do you mean about "Those connectors and squibs on the SRA don't' fall off easy..."?

Also, NO, have only scanned by 2 professional mechanics with good scanners and myself with BlueDriver. Same B1100 Code, resetting comes back right away.
However, my mechanic said the Lexus scanners have access to a back door, all other scanners use the front door. The back door allows for a deeper scan and not only that, he said that only those Lexus scanners will be able to clear the module. However, I think they may just want to sell me the $650 module plus labor so over $1k or close to it.

My thinking at this point (with your awesome help of course and thanks); if I may:

1) Remove both battery cables and short the cables to ensure any capacitors are drained as well as turn the headlights on. I know is overkill but this is a double redundancy measure.

2) Get to the module, inspect the wiring, remove the harness, decide on dialectical grease or ACF-50, or nothing for that matter, plug back in, plug battery in.

3) If the fault is still there, remove the module and send it to MyAirbags.com and they will reset for $50 (or so). I'm just gambling $50 for a possibility.

4) If the fault still there go to Lexus, have the codes read for $150 and do the fix with them and have the $150 applied to the labor.

Any thoughts?
- X

Margate330

The yellow squib connectors and other SRS/ABS component connectors.

You are correct proper handling is required and not for the novice beginner.

Ok so I tried to look up some details and I have 450 pages just for the airbags on my model(RX330) and schematics in my wiring manual too
so it's too much for me to go thru and a lot of the tests are dealer/indy level diagnostics BUT it did mention to look for opens & shorts
in harness junctions, etc- so it is valid for possible bad connection and it does happen.

1) ok- I would wait several minutes.
2) Nothing is my choice but others may have a different approach.
3) I don't know.
4) Yes, or an indy and what I mean by that is not a mechanic with a scanner but rather an toyota specialist mechanic with dealer
level tools and experience so the repair will meet your expectations.

>> I can't help but think there is more to the story on this car- but I hope you figure it out easy and it's something simple so you can get a break.

xcalderon

Thank you,

Would this forum be appropriate and/or good to find an independent certified Lexus mechanic? If no, where could I find in my area? Craigslist maybe?

I also have seen the module on sale at EBay from a salvage cars for $60 or so.would this be a good idea? Maybe I would still need the certified mechanic to program for my car... IDK

Margate330

Hi xcalderon,
I am not an expert on airbags that's why I recommended a specialist because they would scan deeper for airbag, etc codes from other components
that could lead to the B1100 code you are having- while other mechanics would just throw a replacement center assy into it hoping and praying for a fix...

My airbag info is for rx330 otherwise I'd offer to send to you but this is from my manual so yours is prob similar and I made some important notes for your consideration.



Hopefully others can join in and add more info.

xcalderon

Hi,
Thanks so much. I got to see the sensor and has part number 891700E021. eBay lists them for 04 RX330 through 09 RX350 so most likely is the same as yours. In the circuit description you sent seems like there is more text after "...it judges wheather or not the SRS should..." If there is more text would you be so kind to send?
Great points about have it scanned by dealer if we just cannot figure it out. Worth the try though. Thanks again, Xavier

xcalderon

I was able to get to the Center Airbag Sensor Assembly. Harness and connections seem good by visual inspection. However, there is a yellow block on the far right with a triangle and an exclamation sign. Seems like it has a tab and this "plug" could be removed. Would this be a fuse maybe? Would it be safe for me to remove and if a fuse test? Of course, battery off at all times. See picture of the same module (not mine as I didn't take out yet).

Nad1370

DO NOT TOUCH this..!!!
That Exclamation point warning is there for a reason.

xcalderon

That is what I thought so I didn't touch, however, do you know what is it and what it does?

I've seen some modules on eBay without it, but there is no separate OEM part for it so oh boy, let's be careful here. Thanks!

Nad1370

I honestly dont know what thats for.
Its probably just a dummy plug.
If you take it off, there's probably no terminals in there.

But i think you're in the right track with this.
No other codes but the SRS malfunction is usually a failed SRS ECU if no damage on the harnesses.
Only way to clear the code is to replace it.