As others have said above, make sure you have a good battery first.

Power for both the airbag module, and gateway module are both supplied from the rear junction box ( BCMB), so it could still be a bad eeprom in the BCM or BCMB, so you really need to get someone with JLR SDD to scan the car, and check the VIN number stored in each module, as well as run a network diagnostic. If the VIN is scrabled in BCM or BCMB it's likely that the gateway, and airbag modules are just not getting powered up. Otherwise perhaps a faulty gateway module is preventing proper communication between medium speed and high speed CAN buses. ( But SDD will be required to program a new module in any case, so best look into it first! )

 

Repair shop determined the RJB is defective

Does anyone happen to know if a used one can be reprogrammed to my car's VIN?.

 

Up thread you mentioned that you could not get the brake lights to come on regardless of how hard you pressed the brake pedal?
Did you fix this? Or is the bad RJB causing that problem?
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The water in the RJB was the issue.... replaced that and all was fixed.

For everyone that needs in the future, you CAN reprogram used ones as long as the model is the same. They are VIN coded so if you can find a repair shop with the JLR program, you can have it reprogrammed.

 

Thanks for the added info on the CJB/RJB. That will save somebody a bunch of money. Of course finding the right part might be a battle.
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I am having a very similar issue. I had disconnected my battery to do some work in the engine bay, and when I reconnected it (about 30 minutes later), the car didn't recognize my Smart Keys. I tried placing the Smart Key under the trunk/fog light switches as the manual suggested, no luck. I had it towed to the dealership last night and they're telling me it's $7,700 USD for a new Central Junction Box. From what I'm reading above, I should first check the battery voltage. Assuming it's optimal, what are my next steps? Find a replacement with the same model number and have it reprogrammed? I don't want to assume my issue is due to water ingress since this was all caused by a battery disconnect/reconnect, so something in the process of doing that caused this issue.

 

Explained here.....https://ibb.co/w7DR9jz

 

Thanks, I did see that. Is that just "the way it is"? Or is there a way around having to get two (2) new modules?

 

You can recover this, but will come back everytime you disconnect the battery.

This was taken from FB........
​​​​​​Jaguar XF remote lock/key not recognised issues.

I've been getting many requests from the group via word of mouth and I've done quite a few.

Issue one most common:

Car won't lock after battery disconnect. This is solved via immobilisation in SDD.

Issue two less common:

Key not recognised at all hence no ignition, immobilisation not possible.

This is done via cluster reprogram as it will bypass the key sequence, turns ignition itself and do the immobilisation at the end.

This will also update cluster to latest software, bonus.

Please don't throw suitcases of money on KVM module/keys and what not, I've never seen a faulty KVM module.