L322 LIN bus

I've got a couple of BCM errors, LIN bus B - bus off (B1088 type 88) which is currently historic and LIN bus A - short to power or ground (B1087 type 88) which is currently intermittent

What is LIN bus and what does it do? There's reference to central junction box, left side steering wheel module and analogue clock module for A and central junction box, rain sensor, battery backed sounder and interior motion sensor for B
They both refer to the central junction box.. but what does that do and where is it? Does anyone know? guess this is the source of the error codes?

I don't have any other related error codes or symptoms other than rain sensor intermittently working

LIN is effectively a single wire serial, low speed CAN I'm guessing you have a 2010 onwards L322? which is a shame as I only have the 2007-2009 wiring diagrams. The CJB is essentially an addressable fuse & relay box where outputs can be switched by data input, it also acts as a 'gateway' in some cases. The source of the error could well be one of the LIN connected modules or a harness splice having water ingress and pulling the 'network' down or corrupting it - from your last line above, it's very likely the rain/light sensor (or water ingress to it's harness connector) would be a good place to start.

Thank you! Yes it's a 2012
Story.. Rain sensor worked fine until autoglass changed the screen, since which it's sometimes worked but mostly not. The light sensor part is ok.
They replaced the screen again allegedly OEM (thicker) and replaced the sensor but still mostly doesn't work.. either not at all or will randomly stop while in use

The sensor connector looks ok with no obvious water damage and I've never seen an error code for it other than when i got cheesed off with AG and unplugged it, but I've since cleared that code

I've just read that the CJB is also referred to as the BCM.

I'm using SDD which seems to work fine, apart from 'failing to communicate with BCM' and deems all CCF sources to be 'invalid'. Wonder if it's related

Have they damaged / trapped the sensor wiring? used to be quite common...
Is your SDD working OK on MS-CAN? that would give those issues.

I can check the wire for obvious damage/crushing.

What is MS-CAN? sorry still learning

Medium speed CAN, it's common for clone interfaces to not play nicely on that CAN, something to do with pin 13 being connected on the OBD port IIRC

Edit:- it's HS-CAN (ch) - High-speed chassis CAN not MS-CAN

Graculus said:

Medium speed CAN, it's common for clone interfaces to not play nicely on that CAN, something to do with pin 13 being connected on the OBD port IIRC

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Gotcha that's the 2nd line of modules listed can-ms
How do i know if it's working? I get the little green ticks etc on all 3 lines.. i took a pic a while back...

The photo shows the BCM communicating - is that still the case? I'd also be checking there isn't any water into or onto the BCM due to a poorly resealed windscreen....

Ooo ooo i got a new error message, poking around in the options and it replied 'invalid vehicle identification in config' or something like that

Graculus said:

The photo shows the BCM communicating - is that still the case? I'd also be checking there isn't any water into or onto the BCM due to a poorly resealed windscreen....

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That was the last time i looked i forgot to take a pic this time, it had an 'i' instead of a tick because of the DTC noted in the first post.

BCM is under the dash somewhere i think. Can i see it if i open the glove box to get to the fuses?

That is the BCM - it should look like this

Graculus said:

That is the BCM - it should look like this
View attachment 310202

Click to expand...

Ah. I thought that was a fusebox. Silly me!!

Well I've just had a look and it all looks nice and dry in there, so that's good

I've just been out after clearing the codes and neither are currently showing and bcm has a green tick again.. I'll check in a couple of days

It's quite a useful bit of kit, it can be addressed / programmed for all variations to avoid having lots of different vehicle wiring harness' to cover the possible combinations - such as auto or manual wipers, Scandi DRL's, American lighting requirements etc.

Graculus said:

Medium speed CAN, it's common for clone interfaces to not play nicely on that CAN, something to do with pin 13 being connected on the OBD port IIRC

Edit:- it's HS-CAN (ch) - High-speed chassis CAN not MS-CAN

Click to expand...

i accept the cable i have may be no good and not capable of doing everything it claims, but when the garage have corrupted the CCF when they neutered the DPF?
I dont know what they did or how they did it, maybe they didnt know what they were doing - i wouldnt be surprised. could that explain "invalid vehicle identification in config", or simply the cable is no good and i need to get something better?
I'm guessing a proper one is too expensve, so gap-iid is probably the sane choice?

The Supervisory module for the DPF is the PCM, there should be no need for them to edit the CCF as its not a value stored in there anyway.
Other than the LIN DTC's, what's the issue that you need to edit the CCF for?

Graculus said:

The Supervisory module for the DPF is the PCM, there should be no need for them to edit the CCF as its not a value stored in there anyway.
Other than the LIN DTC's, what's the issue that you need to edit the CCF for?

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thanks. i think the DPF has been fudged rather than switched off because theres fake/static values in place.. presumably to tell the car never to regen, as opposed to say it doesnt have one. Unless thats the right way to do it?

specifically, i wanted to see why the reversing sensor doesnt switch off when towing electrics are plugged in.. i know its a small issue.. but thought it would be an easy fix

i tend to check DTCs every 2-3 months just because.. why not...

kermit_rr said:

thanks. i think the DPF has been fudged rather than switched off because theres fake/static values in place.. presumably to tell the car never to regen, as opposed to say it doesnt have one. Unless thats the right way to do it?

specifically, i wanted to see why the reversing sensor doesnt switch off when towing electrics are plugged in.. i know its a small issue.. but thought it would be an easy fix

i tend to check DTCs every 2-3 months just because.. why not...

Click to expand...

One step nearer a nervous breakdown by the sounds of it