Which control module does what?

**monzaz** · 10-14-2017 05:26 AM

Have been trundling around for a while now with brake lights and headlights on permanently....They only switch off when I disconnect the battery. Water WAS coming in on drivers side (GB), passenger floor seems dry. There's a delay on wiper function and dash illumination when I start up as well. Before I attack it I'm just asking if I'm right in suspecting that the CECM? under the bonnet in the Plenum? chamber on the driver's side controls the functions I've mentioned?
It's likely that the water ran through the mass of wiring running into the car on that side so there may be issues amongst that lot, but initially I'd like to make sure I'm investigating the right module. Advice much appreciated.

**A41.8TB6** · 10-14-2017 05:38 AM

Sounds like cecm from your description. I just experience that not too long ago.

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**Nollywood** · 10-14-2017 05:52 AM

Typical CECM fault.

It's under the dash, behind the driver's knee bolster.

I have a spare one from a 2003 B6 A4 Quattro Sport, if you get stuck for one.

**A41.8TB6** · 10-14-2017 06:05 AM

Also doesn't hurt to check your ccm also since your at it. Its underneath the driver seat. I have to replace mine on both occasion. Also start cleaning your rain drainage to prevent future water sippage inside your car.

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**EuroxS4** · 10-14-2017 07:12 AM

Comfort module under the carpet is probably floating in water.Repair water leak and replace module if needed.

**monzaz** · 10-14-2017 10:54 AM

Originally Posted by Nollywood

Typical CECM fault.

It's under the dash, behind the driver's knee bolster.

I have a spare one from a 2003 B6 A4 Quattro Sport, if you get stuck for one.

Thanks 'Nollywood' and thanks to the USA guys although you may be be referring to the CCCM under the dry side on my GB motor. Nollywood... I'm confused now cos I thought the CECM under the bonnet was probably the culprit. Are you saying there's another +++ er which might be responsible? It makes sense cos that's where the water was originally getting in? Again, thanks for all your suggestions.This obviously ain't an uncommon problem.

**A41.8TB6** · 10-14-2017 11:15 AM

All external lightings was controlled by cecm which is common from B6. The one you probably reffering was the ECU/ECM which controll the engine management. The one under the dash usually the driver knee bolster side. I got confuse also when i did mine. Search BCM/CECM.

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**Human Garbage** · 10-14-2017 03:19 PM

The unit under the knee bolster is the Vehicle Electrical System Control Module (J519) and the one under the seat is the Comfort System Control Module (J393). All exterior lights are all controlled by the J519 so you might want to hit up Nolly for his spare or head to the breakers and get another unit.

I try and refer to components by their J or G number as acronyms vary depending on who you talk to... But everyone who was saying you want the unit under the knee bolster is correct regardless of name.

**monzaz** · 10-15-2017 03:36 AM

Many thanks everybody...HG you're certainly right about confusion about the acronyms, You tube has given me a few 'bum steers'. When you say say 'knee bolster'. OK I'm a 'thicko', but on a UK motor are you talking about right or left hand side of the footwell? Is it adjacent to the fuses/relays?

**A41.8TB6** · 10-15-2017 06:13 AM

It should be behind the fuse box. So you should remove the bolster to get access to it. It should be the opposite of the glovebox.

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**monzaz** · 10-15-2017 06:25 AM

Originally Posted by A41.8TB6

It should be behind the fuse box. So you should remove the bolster to get access to it. It should be the opposite of the glovebox.

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Thanks A41. Haven't removed it yet (seems I've got to remove the fuse panel to access one of the fixings), but I've accessed it. On the adjacent mounting there's a stamping
8EO937503. Does that sound like it's serial number?

**A41.8TB6** · 10-15-2017 06:38 AM

Should also have a suffix next to it also. If you ever replace it make sure its identical or close.

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**A41.8TB6** · 10-15-2017 06:39 AM

Open it see whats going on inside. So you have a idea what just happen.

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**monzaz** · 10-15-2017 07:25 AM

Originally Posted by A41.8TB6

Open it see whats going on inside. So you have a idea what just happen.

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Will do. I'll attack it tomorrow when I've got a clear day. Your advice is much appreciated.

**monzaz** · 10-16-2017 07:00 AM

Originally Posted by monzaz

Will do. I'll attack it tomorrow when I've got a clear day. Your advice is much appreciated.

A bit further forward but just 'weathered off'. It's obviously the J519, when I dropped it down some water dripped out and now it's disturbed, other stuff has gone haywire and I've lost my indicators. As it's not driveable I'll disconnect it ASAP and open it up.
One question... securing the aluminium top there are what look like 5/6 rivets. Have these got to be drilled out to expose it?

Nollywood...If your offer is still open, what's the number on that CECM and whereabouts are you? Thanks.

**A41.8TB6** · 10-16-2017 07:53 AM

Should be torx screw...

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**monzaz** · 10-16-2017 09:39 AM

Originally Posted by A41.8TB6

Should be torx screw...

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OOPS, nearly? I'll have a look with my 'seeing' glasses on tomorrow. Spoke to dealer £339 +complications + coding...Managed to get correct number though. 8EO907279F. Just ordered a supposedly kosher one on ebay for £30 so worth a try? Cheers, I'll post results....

**monzaz** · 10-19-2017 06:06 AM

Originally Posted by monzaz

OOPS, nearly? I'll have a look with my 'seeing' glasses on tomorrow. Spoke to dealer £339 +complications + coding...Managed to get correct number though. 8EO907279F. Just ordered a supposedly kosher one on ebay for £30 so worth a try? Cheers, I'll post results....

Halleluia...Module arrived (early). Struggled to unclip original, make sure you've a good light if you have same problem. Forgot to mark 'right way round' on the unit I was fitting. Anyway, I worked it out and connected it up.
Started her up and all working properly except rear wipers on permanently. I haven't had to code it so I don't know whether that will sort it out???
Anyway, it's driveable so yahoo!
PS, forgot to say that wipers don't park, but I think I know why.
Very many thanks to all who helped.