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Discussion Starter · #1 ·
Hi all

Been searching around the forum reading up on the CCM issues. My passenger footwell was wet (RHD), been having intermittent problems with keyless entry, sometimes only the boot opening, then recently intermittent problems with the interior light taking up to 30 seconds to turn off after starting the engine, and then electric windows not working for up to 20 mins after starting the engine.

So... I cleared out the drain plugs in the scuttle pannel (under the battery and master cylinder) and had the carpet up to get the CCM out. Pulled the CCM to pieces down to the circuit board. Circuits look ok, no obvious brown/black areas. So I WD-40d the lot (water displacement spray) and put it all back together. There was some water in the large plastic casing, but not in the plastic casing for the circuit board. Cleaned all that out and WD-40d that too. So onto the wiring.... the outer sheathing (loom wrap) was gone, looked like it had disolved in the water a long time ago. Wires themselves looked ok, and were absolutely mint into the clips themselves. Where the loom wrap had disappeared the wires were a mess so couldn't tell if the splices were bad (and at the time didn't know to look for them). So checked the ground, had that off and cleaned up and WD-40d the loom and ground. After doing all this everything returned to normal for about half an hour. Doors were working fne, interior light turned straight off and windows worked fine.

so....

Parked the car up for about two hours. There was some light rain... well by birtish standards anyway. Went back out to the car, opened the doors remotely no problem. Got in... started the car and the interior light stayed on, windows not working either. At this point I nearly got out and put my bin through the windshield.

So my question is this....

  • Is the CCM toasted?
  • How do I check the wires? What wires should I test, for what voltages, what continuity?
  • Where are the splices located that could be the issue?

I'm guessing that as I didn't completely dry out the carpets that there's a bad splice somwhere that is shorting/has bad continuity. Does this sound plausible? Also what voltage should I be seeing at the ground post?

Thanks for your help guys, much appreciated. If anyone wants to IM me or email on this my address is [email protected]
 

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As with all things, a VAG-COM cable is indispensable for finding hidden error codes. I thought I'd fixed everything on my car until I bought a VAG-COM and pulled down about ten codes from various modules. (Sigh.) It's good to know what the car thinks is going on, anyway.

If you have exposed wiring pressed against wet carpeting, that could absolutely be a problem. Wait overnight and see if it gets better.

Not that this second bit is any help, but damn I'm glad I have no sunroof and the old-style cabin filter housing. I've heard so much bad stuff happening to people who have one and/or the other. Nonetheless, there are far better uses for garbage cans than as projectiles. They're much better suited to being converted into nail bombs -- nobody ever suspects them. Remember it for your next revolution. :lol:
 

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Discussion Starter · #3 ·
Well got to the bottom of it eventually.

All of the splices were toast. The main power splice turned to coper oxide dust when i picked it out of the loom. So several hours later after resplicing all the splices (all of them were coroded to the point of destruction), loom wrapping the loom from the dash down to the rear seat, drying out the carpet and floor pan, spraying enough WD40 to make the car combustable into the void under the carpet and putting it all back everything works.

My advice to anyone with this problem, check the splices in the loom before replacing the CCM. The CCM is in a "water tight" box whereas the loom is completely exposed on the floor pan.
 
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