I do a lot of reading here but simply have not found a solid answer for my issue. I have a 2002 Q45 that has 82,000 miles. Car is in excellent condition and is garage kept. No accidents, not mishaps, etc. Rarely driven at all as you can tell by the mileage.

Recently the SRS Airbag light came on and is blinking. When put into self-diags it codes as one long flash then three short flashes repeatedly. I have double-checked this and it seems to indicate inTrouble Diagnosis that this is "Front LH seat belt pre-tensioner" which I am not sure why it would just fail from sitting in my garage.

I also ran and OBD scanner on it (not CONSULT II) and the OBD scanner is showing an error on FR RH belt pre-tensioner Disconnect which I am thinking why is the ODB showing the opposite side than the self-diag is reporting? Also, I cannot clear the code so I am thinking something is disconnected or faulty.

The pre-tensioners are located in the pillars along with the satelite sensor and then seem to connect to the diagnosis sensor under the center console. My question is what usually goes wrong with these and what should I look I really look at? The circuit seems simple enough and they tell you to check the harness first, but what harness? The pretensioner harness is never moved in the center pillar so what would go wrong with that? I don't see why you would check the seat harness unless it can affect the pre-tensioner in the pillar? If so, I can certainly pull the seat out and check all the wiring, but don't want to waste time in the wrong areas.

If anyone has any experience or suggestions, it would be much appreciated. I hate to simply throw parts at this and don't want to go to the dealer for something simple that I can resolve.

to NICO, at least as a first time poster. Have you tried resetting the light? If so, does the error code come back instantly, or take a while?

Yes, I tried resetting the light. Tried erasing with my code scannner too, but it simply doesn't erase it even though is says it erased successfully. It is the cheap harbor freight Zurich Z13, however it works on other cars fairly well.

I tried the key method several times but I must be doing something wrong. It may be that I am not doing the reset with the key properly. I can easily go into the self diagnostic mode and then back to user mode without issue, but I cannot make that crazy light reset. Unless it is resetting and coming on instantly.

Luchnia wrote: ↑

Mon Jul 09, 2018 8:26 am

... I have double-checked this and it seems to indicate inTrouble Diagnosis that this is "Front LH seat belt pre-tensioner" which I am not sure why it would just fail from sitting in my garage.
...

If anyone has any experience or suggestions, it would be much appreciated. I hate to simply throw parts at this and don't want to go to the dealer for something simple that I can resolve.

Electronics are like that. Their failure isn't related to use sometimes and happens abruptly. Maybe your reset procedure is not working because you truly have a faulty component.

Try the "stomp the brake" test. Even better if you have an understanding partner in the front passenger seat.
Wear a top with ample padding. Get to a safe condition (road, weather, traffic, time of day etc...). At about 30mph or so, panic-stomp the brake pedal.
Did your seatbelt pretensioner tighten the belt? How about the passenger side?

It should be a straightforward test, and you can do it while alone. However, it's best to have a comparison because sometimes the panic stops aren't "panicky" enough by the vehicle's standards so it might not trigger the effect.
If yours alone doesn't do it, then a replacement is the most likely recourse, following any other troubleshooting.
But again, electronics are strange. Disconnecting and reconnecting the harness might just cure it.

I plan to do some more testing this weekend. I will post my results.

Well stranger things have happened. I worked on the Q45 testing the seat belt pretensioners, checking connectors, and so on. I found no problem anywhere. Everything pretty much looked and tested as new.

So I messed around with the ODB II scanning tool and looking at the codes. I said to myself, why not erase the code one final time. I had attempted erasing numerous times and each time showed successful, yet it would never clear. Well this time after the erase the SRS light is off and so far is staying off! I am as clueless on this one, but the main thing is the light is off now and I can get back to other things.

That's good to hear. I hope it stays so.

Sorry I'm not clear on the testing you did; did the belts' pretensioning feature work as expected in a panic stop? Both driver and front passenger, that is.

I just purchased a 2002 Q45 in near mint condition. It had the blinking seat belt sign showing the code via a Matco scanner. I located the wiring harness under the seat, shook it a few times and the light went away. Previous owner has had the issue for months and I just used the simplest solution I could think of to fix it and it worked. For those having this issue, jingle the harness concetor around and/or unconnected and reconnect it (reseat the connectors).

Much later after contributing to this post, I bought a 2003 Q45.
When I got to the dealership for a checkup or some other issue, they pointed out that the vehicle had an open recall (or maybe a TSB, sorry can't recall exactly). This was due to an issue with the SRS system on the passenger side. When I read the details, it seemed to point to a procedure of disconnecting the harness connection, applying somr epoxy to stabilize the wires, then reconnecting it.
I didn't dig too deep since it cost me $0 to get rid of the airbag light on my gauge cluster.

If I find the technical info, I'll add it here. Figured this would help guide more in the direction of self-diagnosis along what raven dealt with above.

Had my issue return. Took it to my local Infiniti and they stated the seatbelt needs to be replaced. They ordered the part and it was all done at no charge. My vehicle has 181,000.