rhythms57

The dealer checked for codes - B0122, B0127 and B1100. They are recommending to replace center air bag sensor and both front seat belt buckle switches - for $1600. The car has $235k miles and the airbags were never used and did not have any front end collisions either.

I read through other posts here. I saw opinions (and the elaborate process) of resetting airbag light is not simple. I plan to try only simple alternatives if possible (not an expert and don't want to play around with airbag system too much). I plan to try the fuse 13 disconnect/connect strategy first.

But the real question is: other than replacing as recommended, what else can I check to see if something simple is an issue? the connections under the seat? - is there a picture to make sure i am tinkering with the right connections? Any other suggestions please?

Thanks very much!

mshumack

I have a single vehicle subscription to Alldata "dyi" for my 2001. There is a lot of information there to help diagnose problems - but they don't list a code B0122 or B0127. A B1100 is the Air Bag Sensor assembly. It is located under the shifter console (on the 2001 RX). It might be worth the $20/yr. for access to this info.

Copy/paste from Alldata...
AIRBAG SENSOR ASSEMBLY


1.Never reuse the airbag sensor assembly involved in a collision when the airbag has deployed.
2.The connector to the airbag sensor assembly should be connected or disconnected with the sensor mounted on the floor. If the connectors are connected or disconnected while the airbag sensor assembly is not mounted to the floor, it could cause undesired ignition of the SRS.
3.Work must be started after 90 seconds from the time the ignition switch is turned to "LOCK" position and the negative (-) terminal cable is disconnected from the battery even if only loosening the set bolts of the airbag sensor assembly.

CAUTION:


- Work must be started 90 seconds after the ignition switch is turned to the "LOCK" position and the negative (-) terminal cable is disconnected from the battery. (The SRS is equipped with a back-up power source so that if work is started within 90 seconds of disconnecting the negative (-) terminal cable of the battery, the SRS may be deployed.)
- When the negative (-) terminal cable is disconnected from the battery, the memory of the clock and audio system will be canceled. So before starting work, make a record of the contents memorized in the audio memory system. When work is finished, reset the audio systems as before and adjust the clock. To avoid erasing the memory of each memory system, never use a backup power supply from outside the vehicle.
- Before repairs, remove the airbag sensor if shocks are likely to be applied to the sensor during repairs.
- Do not expose the steering wheel pad, front passenger airbag assembly, airbag sensor assembly or front airbag sensor directly to hot air or flames.

AIR BAG SYSTEM DISARMING
The Air Bag/Supplemental Restraint System (SRS) incorporates a backup energy source that maintains sufficient deployment voltage for up to 90 seconds after the ignition is turned Off and the battery has been disconnected.
Before disconnecting battery, note radio station settings, since all vehicle memory will be lost. Never use a backup power source from outside the vehicle.

1.Turn ignition to Lock, then disconnect battery ground cable.
2.Wait at least 90 seconds after disconnection before beginning service or diagnostic procedures.

AIR BAG SYSTEM ARMING

1.Ensure ignition is in Lock position.
2.Connect battery ground cable.
3.Wait at least 10 seconds before turning ignition from Lock position.
4.Turn ignition to ACC or On position and ensure SRS lamp lights, then goes off after approximately six seconds. If lamp remains lit, an SRS condition is indicated. Refer to Restraint Systems, Air Bag Systems, Testing And Inspection. See: Testing and Inspection

kalali

Reading your other post, I'm guessing the dealer probably cleaned you out fixing your oil leak, etc. But that been said, the vehicle's active safety system(s) should be addressed quickly and properly. You don't want your air bag(s) not deploy when you need them or deploy when you don't. See how much you "save" if you opt to delay replacing the belt buckle switches and just address the sensor. Or find a local indie shop to take care of it at a lower labor cost. Just my opinion.

Z07

What are the odds that two seatbelt switches and an airbag sensor failed at the same time vs the odds that a single ground strap has broken/corroded causing an open ground?

Any recent repairs of any electrical nature?

rhythms57

Thanks to all the suggestions.
Z07 - anything of electrical repair - well the battery was replaced months ago. Can not recall correlating anything when the airbag light first came on.
Noticing that the light does go off sometimes.
Disconnecting fuse 13 didn't help.
My driver side seat belt has become loose for quite sometime..it does not spring back when released.. it tightens up when manually pulled - can it have anything to do with it?

rhythms57

Thanks to all the suggestions.
Z07 - anything of electrical repair - well the battery was replaced months ago. Can not recall correlating anything when the airbag light first came on.
Noticing that the light does go off sometimes.
Disconnecting fuse 13 didn't help.
My driver side seat belt has become loose for quite sometime..it does not spring back when released.. it tightens up when manually pulled - can it have anything to do with the airbag light on issue??

Z07

If you look under the seat you should find where the seatbelt switch plugs into the wiring harness. Disconnect it and test it with an ohm meter. Open when no belt and closed when belted. I just can't believe that two seatbelt switches that are used differing amounts failed on the same day in the same way.

Does the seatbelt warning light go off when you buckle? If you buckle the passenger seat when empty do you get the SRS warning light for passenger disabled?

I don't think the reel has anything to do with SRS. Reels that fail to retract are a known issue for Lexus/Toyota. They make a slick tape that you can apply to the last foot or so to reduce friction and help it retract. But once the edges start to fray it progresses.

Have you had any problem with wet floors?

IMO trouble codes RARELY point to parts. They do point to diagnostic steps.

If this were my RX I'd figure out if the seat belt switches are really failing to close on buckle. I'd dig into the center lower dash and look for ground straps and disco, clean+scuff and reinstall them.

Tone1499

The following may apply only to my used Lexsus IS250 (2008 model), but I want to describe as a reference, from Japan. It may be a good idea to try one time.

<Current estimation of cause for my car>
It looks like if I touched the knee airbag panel, under the steering, toward up direction and re-start the engine, the light goes away. That panel also has an opening for data retrieval socket for the dealer.This panel is not the panel facing to the dirver with fuel lid switch, but the one lower and facing downward.
I think if this is the case, there is a subtle connection problem, casused by insufficient design, for which the manufacturer is responsible. I called Lexsus customer support group and requested to route this information to the designers.

This is the remedy I took yesterday, after it came on yesterday. My wife told me, she may have touched the panel by her knee, when inserting a parking ticket into the machine from an odd attitude.
Note: This is written in RH sense: Steering is on RH side in Japan.

<Background>
I have a similar problem since I bought the car in April 2011. The light came on steady after purchase, went off, comes on and then off a few times. It remained off before I brought this car into the Lexus dealer for a registration as recognized Lexus used car in May of that year. Since then, no light problem until November 12 this year, when I brought the car into Lexus dealer shop for a routine check. After the check, the light came on, but went off about two weeks later, just before I thought I should call the dealer for a re-check.

First, I thought this is essentially an electrical circuitry problem and searched for information as much as I could. Up to recently, strangely enough, I thought this is somewaht related with the gas filler lid, since there was a case that the light went off after I filled the gas. I have touched all seat belts, dashboards, and looked connectors under the seats. No anomaly noticed so far.

Djpoint

My SRS light stays on steady. While driving. Owners manual says driver or passenger airbag fail. If it flashes, could be side bags or seat belts. Ughhh. I am so done with Toyota/lexus and their glitchy sensors. Any ideas? 2002 lexus rx300 151,000 miles. Also I see in this thread that there are codes. Can that be read by my obd2 scanner?

Does anybody know where i can get an illistration(actually picture) of where front passenger airbag sensor is on 2002 Lexus RX300. Is it under headlight assembly? Do you access it from under the vehicle?

Margate330

It depends on the scanner- most of the cheaper aftermarket scanners will not read Airbag codes as they are just meant for basic OBD data.
Techstream will get the job done and read dealer level data.

Also, if I remember correctly there may a way to get the code without a scanner but I will have to dig and find the procedure unless someone else chimes in and knows how.