Replacing the BCM (09 - Central Control Module)

[Arkious]

Hey chaps,

Drivers side front indicator has began to illuminate continuously today after washing the car. Now first thoughts were water in the wiring etc but I’ve checked the headlight and it’s not that, I then checked the wiring to the headlight and it had 12v on the indicator wire. Having checked the wiring diagrams I seen it goes straight to the BCM, so having disconnected the harness from the BCM there was no longer power being supplied to the indicator.

I presume that this means it is the BCM that is faulty? And if so I’m just curious how to go about fitting it. I have taken the long coding via VCDS but what else needs to be done? Does it need to be a new BCM or can it be a used one?

Thanks very much

 

[henkkeumus]

Hey chaps,

Drivers side front indicator has began to illuminate continuously today after washing the car. Now first thoughts were water in the wiring etc but I’ve checked the headlight and it’s not that, I then checked the wiring to the headlight and it had 12v on the indicator wire. Having checked the wiring diagrams I seen it goes straight to the BCM, so having disconnected the harness from the BCM there was no longer power being supplied to the indicator.

I presume that this means it is the BCM that is faulty? And if so I’m just curious how to go about fitting it. I have taken the long coding via VCDS but what else needs to be done? Does it need to be a new BCM or can it be a used one?

Thanks very much

Well, replacing a BCM is a bit direct but yes, you can do it with a second hand one. Just look for the partnumber (or scan it with VCDS).

So you sprayed water on the car and the blinker automaticly flickers now. I would search for a shortage at the headlight first and check wires/connectors. Maybe some water got into a watertight connector that was not that watertight anymroe gehe.

A new / second hand BCM can be quite exspensive.

 

[RobinA3]

I don't think it could be the BCM that is faulty, if it was then you'd get a load of fault codes for various things.

 

[Arkious]

The light is on static no matter if the car is on or off, and the rest of the indicators work fine with no faults on the car.

As I say, I have checked the wiring back from the headlight and the power is coming from from the harness, which when disconnected from the BCM drops to zero.

I don’t know what else it could be. It wasn’t on when I washed the car but noticed after I had it on tick over to dry out the intercooler etc (which I always do).

No faults on the BCM when scanned with VCDS.

Thanks for the info about being able to use a second hand one I have the part number from VCDS and the unit it’s self and I have recorded it’s current coding. I think it’s just the central locking remote that will need repairing once changed?

I don’t know what else it could be ‍

 

[NHN]

Swap headlights over & recheck.

 

[Arkious]

I’ve checked the wiring on both sides. The indicator wire is permanently live so I’m 100% it’s not the headlight it’s self. It’s coming from the car side.

pin 9 (black/green) is indicator wire on the drivers side and pin 9 (black/white) is indicator on the passenger side. It’s permanently 12V on the drivers side but 0V on the passenger side.

when I unplug the harness from the BCM there’s no longer 12V being supplied to the indicator pin.

So I’m thinking I have a break in two wires or it’s sending 12V out of the BCM from something like a failed internal transistor

 

[henkkeumus]

You can do a check with VCDS.

Go into

[Cent. electrics-09]
[Output Test-03]

And look if you can test blinker function there.
Just like RobinA3 is saying, I don't think the BCM is at fault.

What you can also try is get the battery off for 5 mins and then connect it again.

 

[Arkious]

Tried it and it comes back as completed OK, no faults shown. No faults on BCM and I had the BCM removed for about 10 mins but still no better.

https://www.briskoda.net/forums/top...ndicator-bulb-permanently-on-hids-fitted-ccm/

found this which sounds the same only I don’t know what caused mine to fail but it’s looking more and more likely that it’s the BCM for whatever reason. Kinda glad if it is as it’s much easier to repair than wiring!

 

[henkkeumus]

Tried it and it comes back as completed OK, no faults shown. No faults on BCM and I had the BCM removed for about 10 mins but still no better.

https://www.briskoda.net/forums/top...ndicator-bulb-permanently-on-hids-fitted-ccm/

found this which sounds the same only I don’t know what caused mine to fail but it’s looking more and more likely that it’s the BCM for whatever reason. Kinda glad if it is as it’s much easier to repair than wiring!

The test come out OK on screen. But did you take a look at the blinker when VCDS ran the test? Like when VCDS lets it "blink" does it actually blink or does it keeps burning 'on'? etc..

And yep, replacing the BCM is much easier instead of finding a wire fault, but it's alot more exspensive though gehehe.

 

[Arkious]

The test come out OK on screen. But did you take a look at the blinker when VCDS ran the test? Like when VCDS lets it "blink" does it actually blink or does it keeps burning 'on'? etc..

And yep, replacing the BCM is much easier instead of finding a wire fault, but it's alot more exspensive though gehehe.

just stayed lit read quite a few things online now relating to aftermarket HIDs leading to premature failure with this outcome but mine are factory fitted so I guess it’s just been funny timing!

Ordered a module so hopefully it works!

 

[henkkeumus]

just stayed lit read quite a few things online now relating to aftermarket HIDs leading to premature failure with this outcome but mine are factory fitted so I guess it’s just been funny timing!

Ordered a module so hopefully it works!

If it's the same BCM module just copy and paste the longcode.
Hope it works out for you bud, good luck.