I have searched the forums and found useful airbag warning light information, unfortunately nothing specific to my car. It's possible that other cars' posts might be relevant but I can't know.

When I switch my ignition ON my amber airbag warning indicator lights for approximately 2 to 3 seconds then extinguishes for 3 to 4 seconds then lights again and stays on. No coded flashing messages, nada. A cheap OBD2 monitor displays "No Codes". Can any failure modes be ruled out or in? Other threads for other cars talk about coded flashes, 19 of which (could?) mean the clock spring needs changed. Based on the indicated fault can I be sure the clock spring is or isn't OK? Where do I start, after disconnecting the battery and having a cup of tea?

This is the last on my very long list of MoT failures, I'd be delighted if any of you good and knowledgable people could help me down, Apollo 13 (Houston, it's all gone terribly wrong) stylee.

 

You need to get a Jaguar specific code reader, icarsoft or similar.

 

[QUOTE=kansanbrit;2444617]You need to get a Jaguar specific code reader, icarsoft or similar.[/QUOTE

Thanks for the advice. Amazon has the iCarsoft i930 for 99GBP, is this going to do the job?

 

Also, just a thought - are there any "it might be this connector is loose" easy fixes that I could try - I think there are connectors somewhere in the seats for example. How do I access and identify these, anyone? Any other things I could try?

 

Do all the steering wheel buttons and horn work, consistently.

 

Hmmm, great question. I don't know is the quick answer, the car's been parked up, unused and unloved for the whole of the pandemic. I drove it just a few (no more than 3) times this last week and not far. I haven't used anything on the steering wheel except the turn signals, I just stick it in drive then, erm, drive. I'll go check everything works

 

+1 to diagnostics.

The SRS (Supplemental Restraint System) is complex with many interdependent components. Without DTC's (Diagnostic Trouble Codes), it's simply guesswork. When the ignition is switched on, the RCM (Restraint Control Module) performs a self-test and then performs cyclical monitoring of the system. If a fault is detected the RCM stores a related fault code and illuminates the airbag warning indicator.

Here's the component setup:






There's a lot going on!

However, modern Jaguars are VERY sensitive to battery condition and state of charge. If you haven't been keeping it on a CTEK or similar during the pandemic, I would eliminate battery as a possible cause before proceeding to more esoteric (and costlier) possibilities. Low batteries cause all kinds of weird errors simply because sensors don't receive in-range signals.

Graham

 

Thjanks Graham for such a comprehensive and helpful post. The battery has received only a short fast charge and a couple of jump starts so I'll give that a thorough charge, great advice. If the problem persists I think it's time to get an expert in.

Can anyone recommend someone in / around Glasgow with the appropriate skills and diagnostic tools to fix this for me at a fair price?

 

[QUOTE=2010XFS;2444620]Yes

 

Light came on my 2012 turned out to be clockspring

 

Prestige Jaguar have recommendations from Glasgow based members.
https://www.prestigejaguar.com/

Graham

 

Yes, I used them before. I've called them many times this week and they aren't answering the phone and aren't returning emails. Weird. I ordered the diagnostic reader today, I'll update with error codes. I have fully charged the battery, the indication remains.

 

Yes, they seem to. The car is off the road so there's not much I can do in terms of a full road test but everything seems OK. Thanks for the input.

 

Oops . . . this was in response to "do the column controls work"

 

My iCarsoft i930 just arrived. I pluigged it in, switched the ignition on then ran the automatic diagnostic routine. Under the "Airbag" option the following single DTC was recorded:

U0402 invalid data received from Transmission Control Module

I reset the code, the airbag light stayed lit. I disconnected the i930 and repeated the process. This time no Airbag DTC code was listed and the airbag light stayed on. Clutching at straws I disconnected the battery for two minutes, reconnected then repeated the process. No airbag codes listed, the airbag light is still on.

I now have no clue what to try . . . could the invalid data received from the transmission control module be that module's last gasp before it died, would a dead module result in a lit airbag light and no DTC codes?

 

I was thinking too literally, its an Airbag light problem . . . I think I now found the issue. Under the "Restraints Control Module" menu (not "Airbag") I see the following Code:

B1194 Driver's Side Frontal Accelerometer Sensor

I reset this DTC and the airbag light went out, briefly then came on again. The code persists after repeating the automatic diagnostic test.

This looks like it's probably item 13 in the great diagram Graham posted, mine being a UK model with the steering wheel on that side of the car. I'll go see if I can find a loose connection, any and all tips more than welcome!

 

This is getting weird now, I swapped the driver's and passenger's side sensor, hoping the fault would follow but the reader still reports a Driver's Side fault. So I figured its the harness then just to be sure I disconnected the passenger side sensor and retested. So I now have the passenger side sensor in the driver side and the passenger side has no sensor fitted. The reader still reports only a drivers side problem. I have no clue where to go now. Any ideas anyone, please?

 

Update . . . the Passenger side fault was being reported correctly, I didn't notice it was reported on a second screen. So, I now get the passenger side error if I remove the sensor on that side but the error clears when I fit either sensor, suggesting the sensors are not the problem. The drivers side error is reported regardless of which sensor is fitted in that position, so probably a wiring issue? Can anybody advise the routing of the loom back to whatever unit it connects with? I really was hoping it was a knackered sensor :-(

 

This is for RHD vehicle.

 

Thanks everyone for your help. I found the problem, one of the wires to the Driver's side crash sensor had a break in it, the insulation jacket was intact but there was a "floppy" section. I stripped the jacket off and joined the wire ends together. I was concerned that the wire might have been ok and that I broke it when I was stripping the jacket. So when the ignition was turned back on I stared at the airbag light in disbelief. I'd been watching that damned light for the best part of three days and my instinctive reaction to it staying off was that now the light's broken what next?!! Thanks again!