What is the car?

Was it all working before you took the car to the garage for the mot and service?

What codes were thrown up when scanning? The part number you supplied is for a cjb/bcm

I bet the problem is water ingress. Have you physically looked at it? It's located behind drivers right hand side footwell trim.

You can replace the cjb/bcm with a used one, but it entails some work with JLR software, SDD. Numerous cjb/bcm on the used market, like ebay etc.

I also belive some work will be needed to be done on the circuit board itself to flash you vin number to it. @sportbrakePhil will indulge you further I think. He is a whiz on the finer works on electronics and circuit boards.

 

I also belive some work will be needed to be done on the circuit board itself to flash you vin number to it. @sportbrakePhil will indulge you further I think. He is a whiz on the finer works on electronics and circuit boards.

I've no idea if the pre-facelift BCMs require a BDM programmer for that unfortunatley, or some other style of programmer, or for that matter what SoC the use that you'd need support for, perhaps it's a good sign there's not loads of info online about the earlier ones and idicates they don't corrupt so bad you can't deal with it with SDD ( or at least not regularly ) - or maybe the info is out there, and I never had cause to look, as my car is a facelift.

 

Hi Alex and thanks for the quick response.

My car is a 2010 3.L V6 diesel XF and while awaiting a response, i have found one company that have part C2Z15084 and was described by the JLR technician as a central (front) BCM located beside the driver's foot, which will cost over £600 and a response form a BCM repair company who have quoted £200 for a repair in a 48 hour turnaround.

He also mentioned he saw a tiny amount of rust which could explain the issue, plus the fact the battery had been allowed to run flat while up on the ramp with the local garage.

The car has had a mystery battery draining issue since i acquired it back in 2015 and will not start on the 6th/7th day of not being driven.

regards,

John

 

hi Alex.

the codes you enquired about are:

U0140-00 FACP 102.907mi lost communication with body control module which the JLR technician said may be responsible for the seven items below, which may/should come back online once the above is repaired/replaced.

ECUs not responding
AAM
ACM
APM
DABM
FCIDM
NCM
TEL

regards,

John

 

Yeah sounds like some sort of catastrophic failure of the module we discussed. Basically if this goes, it indeed does have a knock on effect with many sibling modules.

Rust? Rust inside the module? Have you looked at it yourself? Photo of it?

Oh no.....the battery went flat did it. Hmmmmm that could have caused the bcm to corrupt itself. This is a major headache with the x250 and appears time and time again. The bcm is so so sensitive to electrical interruptions, a really poor electronic design for sure.

How old is the battery? Should have a date hot stamped into the battery case plastic or a sticker denoting date. Have you checked the voltage of the battery at rest....should be @12.6v and no lower. If it is lower then the battery has gone bad. With the engine running if you check the battery again it should be @14.5v. If any lower it would indicate that the alternator is on the way out and not providing battery with sufficient charge. Bad batteries and alternators are also killers of bcm's!

So you took the car to a main dealer? Presumably then SDD (JLR's own software) was used to scan the car? Don't whatever you do in future go to a main dealer, if indeed you did. They will rob you blind and replace things that can be repaired. Find an independent Jaguar specialist near to you. They will charge you a fraction of the cost and are in most cases more knowledgeable than the main dealer!

£200 is really not too bad to look at and repair the bcm, if this is the problem. I'm so interested to see a picture of it if you can manage that. Especially closeups to see if there is any furry corrosion.

 

Also U0401 is reporting that either:

An inability to communicate with the BCM

Or

The BCM is not able to communicate with the ECU.

 

I take it all the 'simple' stuff was checked by the garage? Like the BCM earthing, ECU earthing, wiring between the two for continuity and if you told them about your starting issues, then the battery and alternator as already discussed.

 

I can only assume it was but they also did a full diagnostic on the car and gave me the report.
when they could do no more, they recommended the auto electrician who was stumped too, so recommended i go to Jaguar.
when i originally went to collect the car from the local garage, I was informed that the battery was dead and saw them take a battery off the shelf to start my car with, as i thought perhaps they might have jump-started it and blown some fuses. I then responded that you've had it up on the ramp for over a week and it usually won't start after 6-7 days of inactivity but i don't know that they've checked the alternator.

In answer to an earlier question yes, the car was in full working order when left with them.


regards,

John

 

hi.

The battery is only just over a year old from memory.

I now have a little device plugged-in to the cigarette lighter socket which tells me how much voltage is available prior to ignition and then when running which is around 14.5v but i think it's lower than 12v prior to ignition.
yes, JLR used their own equipment to scan the car and this was £200 + vat.

Not seen the rust with my own eyes, just going by what the JLR technician said but will try and get a photo tomorrow during daylight.
Jaguar formal result is the non-functioning BCM is no longer made/available.

i would say the alternator, as i have had this problem across three batteries and the current one is a genuine jaguar battery supplied by jaguar.
I had simply put it down the car running so many things when sitting idle and not being driven daily.

an auto electrician i saw before going to jaguar said if I had made the journey i told them about that entailed five stops and re-starts, then this takes a lot out of the battery but that i should be able to leave the car idle for 4-8 weeks without starting it and it should still start!
after doing around 150 miles that day with all the stops, the car was stone dead the next morning, so it points to the alternator in my mind.


regards,

John

 

My feeling is a Jag Indy is in order as it is well out of the 'local garage' league.

 

Find a BCM to match the part number and you can clone the unit, I did a quick google on your part number and Auto Reserve Jaguar have one for sale at less then £100. There are a couple of BCM boxes that will fit your car as there some updates to the BCM on the pre-facelift model.

You can call these places and they will help.

You can find a company to clone, probably around £120 should cover.

After following the battery off process, this is very important, removal is not complicated.

I dont think you need SDD to introduce the BCM back to the car, when I replaced mine I don't recall using SDD.

 

That's good to know for the op.

It's that code that is sort of troubling though. It can be thrown up by two things. I still think the basics need covering before condemning the bcm.

Still awaiting the pictures of the bcm and the 'rust' 🧐

 

The BCM has its fingers in some many areas of the electronics, when I had a faulty BCM it gave codes for a faulty ABS sensor, MAF sensors, numerous wiring issues etc...

All codes disappeared on replacing the BCM.

Weird.....

 

Yeah for sure. Hope it all gets sorted.....cheaply