Lots of errors!!!

[roadtripper]

I might have to squint, make my self thinner and stand on my head in the engine bay lol. I can’t even see the bloody thing, when I replaced the wire and plug I just had to feel around and use the force lol. Even using my phone camera to try and take pictures of the reg came out rubbish, its down in there isn’t it!!!!

I asked for some recommendations on borescopes/endoscopes over on this thread, that might help you see into some of these awkward areas?

Borescope / Endoscope recommendations?

Not for the Caravelle but I have what sounds like a leak in the bathroom upstairs that I could try and see what is wrong by checking the ceiling void in the kitchen below by removing a downlight if I had a reasonable borescope - and I figured with looking after T6s and folk's various trades this...

www.t6forum.com

 

[T6_FunBus]

I also found this video a while back, the guy seems to think the alternator has a ‘failsafe’ mode and just kicks out 14 volts when the communication is broken.

Seems similar to what mine is doing.

Given I’ve tested and replaced the wire from alternator plug to battery module, and that now has continuity and 11v at rest, and tested a new module, i’m not sure what else to think atm

Periodic errors on module 61 also, not all the time, but sometimes return (no signal generator, and no coms with battery module).

 

[T6_FunBus]

I’m starting to think I need to find an electrical specialist that knows transporters, and has a picoscope, VCDS and such to do some proper checks and more in depth analysis, as I’m starting to strugle with what I have tbh and running out of ideas.

I’ll still have a think and if anyone has any more ideas on what to test / look for please let me know - help is appreciated.

There’s no one I know of near me (Swindon) that I’d trust to look at it tbh. But if anyone knows of someone that may be able to help around this area please let me know.

I know the vans working and I can use it, but its annoying, I hate errors / problems and would really like to get to the bottom of it and have it fixed!

Cheers.

Oh I also saw this after a blast last night to blow the cobwebs out.

I wonder if the alternator is faulty / on its way out and is causing some gremlins?

 

[roadtripper]

@Absolut5 is based in Salisbury which, while not next door, isn't miles away and may be able to help.

 

[T6_FunBus]

Thanks, I thought they focused on audio and retrofits, not repairs, I’ll have a look.

 

[roadtripper]

Thanks, I thought they focused on audio and retrofits, not repairs, I’ll have a look.

I think they do but worth an ask

 

[T6_FunBus]

Just for my own sanity I went back again, and bypasses the new wire I fitted, just to be 100% sure it was not pinched when I put it back into the sleeving and rerouted it with the original.

The result is the same.

I also tried output test and across the battery it showed 14+ volts before and same during test, so no difference.

On starting I get immediate ‘error - start stop’ message in cluster.

This time I had battery regulation control module error (which cleared).

Voltage was 12v upon start and idle, if I rev the engine it then kicks in at 14+ volts and just stays there.

Does anyone know if there another signal / com wire going to the alternator from the bcm? Other than the one I have already replaced?

If not then the only thing I am back to thinking is the alternator is at fault. What a bloody annoying problem.







Almost impossible to get to the alternator sticker but maybe part of the number provides a clue lol.

 

[Lightrofit]

Just for my own sanity I went back again, and bypasses the new wire I fitted, just to be 100% sure it was not pinched when I put it back into the sleeving and rerouted it with the original.

The result is the same.

I also tried output test and across the battery it showed 14+ volts before and same during test, so no difference.

On starting I get immediate ‘error - start stop’ message in cluster.

This time I had battery regulation control module error (which cleared).

Voltage was 12v upon start and idle, if I rev the engine it then kicks in at 14+ volts and just stays there.

Does anyone know if there another signal / com wire going to the alternator from the bcm? Other than the one I have already replaced?

If not then the only thing I am back to thinking is the alternator is at fault. What a bloody annoying problem.

View attachment 216091

View attachment 216092

View attachment 216093

Almost impossible to get to the alternator sticker but maybe part of the number provides a clue lol.

View attachment 216094

I can see the Valeo brand in that pic but yes, the part number does confirm your alternator is 03L 903 023 L so your regulator is 03L 903 803 C

The only comms wire is the LIN that joins in with the sensor on the battery

 

[Lightrofit]

C = Alternator
A = Battery
J367 = Sensor unit on battery NEG terminal
D218 = LIN wire

 

[Lightrofit]

J519 = BCM

 

[Lightrofit]

Fuse SB35 (In little fuse box under bonnet, next to coolant bottle
J623 = ECU
J317 Terminal 30 relay, inside Ebox under battery

 

[T6_FunBus]

I can see the Valeo brand in that pic but yes, the part number does confirm your alternator is 03L 903 023 L so your regulator is 03L 903 803 C

The only comms wire is the LIN that joins in with the sensor on the battery

I’m a little confused, I cut the connector off of the old wire at the source (alternator) then I cut the lin wire near the plug on the battery and connected to the terminal, bypassing 99% of the old wiring.

Looking at your diagram, does this mean the green / yellow lin wire was also spliced into / joined somewhere under the battery and going to the BCM? I figured there was another wire going from BCM to alternator.

If so I’ve cut that signal off by bypassing pretty much the full length of the wire??

Sorry if I sound stupid, but if the battery module is connected only to the alternator, how is that reporting anything back to the BCM?

Confused

 

[Lightrofit]

I’m a little confused, I cut the connector off of the old wire at the source (alternator) then I cut the lin wire near the plug on the battery and connected to the terminal, bypassing 99% of the old wiring.

Looking at your diagram, does this mean the green / yellow lin wire was also spliced into / joined somewhere under the battery and going to the BCM? I figured there was another wire going from BCM to alternator.

If so I’ve cut that signal off by bypassing pretty much the full length of the wire??

Sorry if I sound stupid, but if the battery module is connected only to the alternator, how is that reporting anything back to the BCM?

Confused

Correct, the LIN is 1 wire that connects all 3 to each other and is spliced. So 1 wire from BCM to both battery sensor AND Alternator.

Sorry, should have added that bit of info earlier, I wrongly assumed it was a known factor ha!

 

[T6_FunBus]

Correct, the LIN is 1 wire that connects all 3 to each other and is spliced. So 1 wire from BCM to both battery sensor AND Alternator

Balls, so I may have fixed the damaged wire, but connected the alternator up to the battery module, and under the battery tray where ut gors to bcm, cut that connection off.

A quick dirty way to test would be to strip and connect the old lin wire to the soldered joint of the new wire near the terminal (assuming the dead-end of wire connected to it still will not cause an issue).

 

[Lightrofit]

Balls, so I may have fixed the damaged wire, but connected the alternator up to the battery module, and under the battery tray where ut gors to bcm, cut that connection off.

A quick dirty way would be to strip and connect the old lin wire to the soldered joint of the new wire near the terminal (assuming the dead-end of wire connected to it still will not cause an issue).

At this point I would make an entire new connection to the BCM and connect that, routed outside the van just for testing, and see if it clears the faults. If it does, then you know it's worth all the wire repair effort before doing it in all the awkward places.

The BCM is accessed easily enough, tap a wire to the correct pin and then join it to alternator and battery wire that you've added.

 

[T6_FunBus]

Spot on, thanks for the diagrams and help, its the best lead I have, so I know what I’ll be doing tonight. Fingers crossed!

 

[T6_FunBus]

So I did a test on the wire, the old one at both ends is showing 3-4 volts at rest with ignition on or off, wheras I understand the lin should show 11v at rest. I did also bridge the wires in a complete loop as I had access to them but no difference.

So as you said, its dashboard apart to get to the bcm and make a new connection.

I may just be really unlucky and even if I fix this connection the error persists!

I have seen you can get to the bcm from the bottom but that looks like I cannot access the connectors.

 

[Lightrofit]

So I did a test on the wire, the old one at both ends is showing 3-4 volts at rest with ignition on or off, wheras I understand the lin should show 11v at rest. I did also bridge the wires in a complete loop as I had access to them but no difference.

So as you said, its dashboard apart to get to the bcm and make a new connection.

I may just be really unlucky and even if I fix this connection the error persists!

I have seen you can get to the bcm from the bottom but that looks like I cannot access the connectors.

The honest truth is they aren't terrible to get to but you do need a good bend ethic.

If you have an extra 2min, you could whip the clocks out and then the connectors are easily pulled up and accessed

 

[T6_FunBus]

The honest truth is they aren't terrible to get to but you do need a good bend ethic.

If you have an extra 2min, you could whip the clocks out and then the connectors are easily pulled up and accessed

Lol thanks, time to stand on my head in the footwell then. Do you know if my assumption is correct, that the lin wire from the bcm should be more healthy at rest?

 

[T6_FunBus]

Well I got to the bcm wiring easy enough, but can’t get the locking tabs of the connectors.

Also trying to work out which no wire it is on the black connector.