Another update to keep this alive. Still no resolution and dealer still have the car. Apparently, they were unsuccessful in resetting the CJB though they claim a hard rese was performed and all other functions work as expected. I spoke the service manager and he has agreed to contact the Jaguar factory technical assistance engineer. My fear is that their dealer tech (working on a flat rate basis), has no interest in this endeavor. Unfortunately, it would appear we don't have a Motronics operation here in the States. They apparently do have industrial operations, but I think different focus. Purchasing a used CJB is not a good option. The wiring diagram is helpful and though I am loath to break open the harness I may have no choice. Obviously its lucky we have other vehicles as we are now going on two weeks with car sitting at the dealer and over a month of me chasing theories. To be continued as progress allows.
Bond
2012 XF

 

Sorry to read this. My headlamp was also not working and 5 people at the workshop didn't found a solution, so i took the lead in the analysis and found out that many connectors where full of oxidation. They seem to have a thin film layed over the pins during the years. So i decided to clean all pins with Isopropyl (also the ones on the headlights) plugged every connector back in and tadaaaa: i had back my lights.
I would suggest that you measure the cables with a wire-bridge on the one side and a multimeter on the other side. I did the same to make sure the cables are in good shape. btw: I unplugged the battery more than one time and never had a problem.
So give it a try
If the cables are okay do the following:

1. open all doors and the trunk
2. unplug the battery
3. remove every plug from the cjb and headlamps
4. remove the cjb
5. clean all pins (isopropyl and q-tips)
6. Clean the plugs (with air pressure)
7. reassemble the whole thing in reverse direction
8. fingers crossed

:-)

 

Have you contacted Motortronics? With what you have gone thru I would consider using them? They claim they can fix your CJB for 200 GBP. They might very well ship to the US?
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Thanks guys,
good advice on both counts. So here is latest update. After the dealer at my request contacted the factory "TA" the TA began trouble shooting with the dealer's tech online. Final diagnosis is as you might have already guessed is a faulty CJB. The dealer offered to sell it at wholesale price and an all-in price of $4700.00. Breath taking, eye watering and honestly no great surprise at this point. I accepted their offer, and the part arrived this past Friday. After many weeks of efforts, parts and several diagnostics not to mention lost sleep and not having the use of the car, I am simply over it. Plus I wasn't sure what it would have cost if I declined the offer.

Thanks guys,
good advice on both counts. So here is latest update. After the dealer at my request contacted the factory "TA" the TA began trouble shooting with the dealer's tech online. Final diagnosis is as you might have already guessed is a faulty CJB. The dealer offered to sell it at wholesale price and an all-in price of $4700.00. Breath taking, eye watering and honestly no great surprise at this point. I accepted their offer, and the part arrived this past Friday. After many weeks of efforts, parts and several diagnostics not to mention lost sleep and not having the use of the car, I am simply over it. Plus I wasn't sure what it would have cost if I declined the offer.

As I don't yet have it back, I guess time will tell. At this point I believe the dealers mechanic did not do all he claimed, and as a result I may have purchased a very expensive replacement headlight assembly that was not needed. So do I reinstall my original assembly with new bulb/ballast and take chance of corrupting new CJB or install the new one. A neighbor who was the factory Ford "TA" recommends I install the new one. I guess it makes sense as I can't send it back and don't know if/when I could sell it.

So, stay tuned for my final verdict once I have it back and reassembled.

bond
2012 XF

bond
2012 X

 

Thanks guys,
good advice on both counts. So here is latest update. After the dealer at my request contacted the factory "TA" the TA began trouble shooting with the dealer's tech online. Final diagnosis is as you might have already guessed is a faulty CJB. The dealer offered to sell it at wholesale price and an all-in price of $4700.00. Breath taking, eye watering and honestly no great surprise at this point. I accepted their offer, and the part arrived this past Friday. After many weeks of efforts, parts and several diagnostics not to mention lost sleep and not having the use of the car, I am simply over it. Plus I wasn't sure what it would have cost if I declined the offer.

As I don't yet have it back, I guess time will tell. At this point I believe the dealers mechanic did not do all he claimed, and as a result I may have purchased a very expensive replacement headlight assembly that was not needed. So do I reinstall my original assembly with new bulb/ballast and take chance of corrupting new CJB or install the new one. A neighbor who was the factory Ford "TA" recommends I install the new one. I guess it makes sense as I can't send it back and don't know if/when I could sell it.

So, stay tuned for my final verdict once I have it back and reassembled.

bond
2012 XF

 

Although the solution is not one wants to hear, it is good that it was finally traced and can be resolved. I agree as to replacing with the new assembly. It would be nice to have the old CJB to dissect and see what the physical cause for the issue is.

Love to hear more about your final outcome.

KK

 

RESOLUTION. THE CJB was replaced by the Dealer after consultation with factory engineers. My total cost for this part, diagnosis, labor ($1008.00) and part ($3313.31) totaled $4786.53 with tax and environmental fee. ALSO. Associated cost to me included new bulb and ballast (amazon about $150.00) new complete headlight assembly (eBay $1100.00) one independent shop and the dealer's previous unsuccessful computer diagnosis ($380.00) for a grand total staggering $6,416.53. Not mention my labor to R&R the headlamp, chase grounds, theories, lost sleep and the car out of service for about 4+weeks. All USD.

The old CJB I have on my bench, and it looks as new. No evidence of corrosion, shorts, wicking..nothing! I really don't know how to test but after I recover from my haircut, I may send it off to Motronics for their repair and diagnosis. Thanks to all who contributed. Funny although my pockets are empty, I am relieved to finally have resolution and closure.

bond
2012 XF Portfolio

 

Hey great outcome but terrible cost!!

It would be great if someone did what you described?
I am trying to figure out what goes wrong with these JB's? I mean it can't be a component failure as you can reset them using SDD?
But it appears with another battery change you will be right back at the same place with the same problem?
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