Central Locking Blowing Fuse & Door open Warning

[Dan Glibitz]

Hi. On my 2004 Passat Tdi, the alarm got activated the other day, so I turned it off with the key fob, as per.

All was well, or so I thought, until i tried to lock the doors using the key fob. Nothing happened!. I got the 2nd fob, thinking the battery in the fob must be low but still nowt!

I checked the fuse by the driver's door and it had blown, so I replaced it.

All seemed well, for a day but on a subsequent unlock with the fob, the fuse blew again.

The central locking works fine using the key but yesterday, I got a new error - I'm now getting the warning on the dash that my Driver's Door is open, when it aint.

Any suggestions out there in VW land please?

Many thanks

ps. I've just noticed that I have no interior light and the Fuel Filler flap release is not working. I put a fuse in to No. 14 and I managed to operate the filler cap release, so I can still drive it at least - so I'm guessing it's the CL operation that blows the fuse? Any help to you VW Doctors?

[martin1810]

Sounds like a live feed is shorting to earth. You need to check the wiring to the ccm under the passenger seat and carpet. Unwrap the wires to have a good look. If you don't find anything wrong, the fault may be the drivers door control unit or lock which is behind the armour plate, behind the door trim. If you are not good with electrics you may need an autoelectrician.

[Dan Glibitz]

Sounds like a live feed is shorting to earth. You need to check the wiring to the ccm under the passenger seat and carpet. Unwrap the wires to have a good look. If you don't find anything wrong, the fault may be the drivers door control unit or lock which is behind the armour plate, behind the door trim. If you are not good with electrics you may need an autoelectrician.

Thanks for the reply.

sorry to sound dumb BUT . . . . what's a CCM? and do I need to remove the passenger seat to access it?

Thanks

[martin1810]

ccm = convenience control unit. All the convenience functions like central locking, alarm, interior lights etc run through it. It is connected to either 2 or 4 door modules (depending on model). It is this unit that acts on the key fob signal to unlock doors. Your fault sounds like it might be door module related rather than ccm. Do a search on here for wet carpets. That will get you lots of info and help.

[Dan Glibitz]

Thanks again Martin1810 . . . . . . Where is this "Door Module" located and what does it look like please?




Well, just removed the passenger front carpet and it is wet down there, not soaking or standing but enough moisture to bead up on the metalwork and soak the cloth tape round the loom that goes to the ccm thingy.

the water is clean.

Inside the ccm, it is bone dry.

I've removed the pollen filter, dry and very clean, as was the area under it.
I've removed the battery and cleaned out the drain plug under the battery tray (Which was semi-clogged with dry leaves)

Does this ifo help anyone with a clearer diagnostic?

I'm going to dry the loom with the hair drier and see what happens . . . .

Being as the fuel filler, interior light, windows work ok when I replace the fuse and it blows when I use the key fob to unlock (And I've got the "Driver's door open" warning on the dash) does anyone know which colour wire I should pay special attention to when checking for faults under that there carpet?

Or does the fault lie elsewhere? and the wet carpet is a pink mackrel?



Thanks

The plot thickens . . . . . after re-connecting the battery, the open door warning light has gone out

[martin1810]

Sounds like the ccm should be ok if the fob is opening all the doors and boot. If it is the key that causes the problem it suggests the door lock module is the problem. It is inside the drivers door. It could be a wire from the door to the ccm though. Check the wires where they go from the "A" post into the door.

[Dan Glibitz]

Sounds like the ccm should be ok if the fob is opening all the doors and boot. If it is the key that causes the problem it suggests the door lock module is the problem. It is inside the drivers door. It could be a wire from the door to the ccm though. Check the wires where they go from the "A" post into the door.

Hi again Martin 1810.

Yes, the remote locks everything ok and all the other bits work ok (Fuel filler, interior light, windows) but it seemd that when I opened the doors with the remote, the fuse blew. I've just ordered 10 x 10A fuses from fleabay, so I can get a better picture of just what's happening.

Interestingly, when I unlock the doors with the key, the boot (Tailgate) does not unlock and I have to do it manually. All the other doors lock & unlock with the key, as they do with the button on the driver's door armrest switch.

If I recall correctly, this all started when I'd left the car with it's windows down and I'd used th fob to lock the car up (Also setting the alarm). When I returned to the car, I passed very close to the open window and the alarm triggered. I immediately turned it off with the fob, with the "Double click" that I always do to open all the doors. From this time on, it seems like the double click is the time when the fuse blows - though I'll thoroughly test this when the fuses arrive. I wonder if a single click leaves the fuse intact and if so, what does this mean?

I'll report / ask further over this weekend but thanks a million for your help so far.

[martin1810]

If you can narrow down "exactly" which sequence blows the fuse, I may be able to give more detailed help. The tailgate not unlocking is common and usually ends up being a faulty lock but it can be a damaged ccm wire.

[Dan Glibitz]

If you can narrow down "exactly" which sequence blows the fuse, I may be able to give more detailed help. The tailgate not unlocking is common and usually ends up being a faulty lock but it can be a damaged ccm wire.

Will do Martin.

Just as soon as my bulk pack of 10A's arrive!

The tailgate not unlocking on the key is a new one as it's always unlocked before using the fob.

The carpet's up and drying out so as soon as the fuses arrive, I'll test for the exact sequence and post back.

being without window operation and remote locking is like having your right arm chopped off . . . . . . how did we ever manage before we got so lazy?

[Dan Glibitz]

so, my fuses arrived and I fitted one . . . . . .

Interior lights, windows, fuel flap all work fine.

Gingerly locked it up, using the fob . . . all's well

Unlocked the driver's door with a single fob-click . . . all ok, fuse still inact.

Locked it again and tried the double click to unlock all doors and the fuse didn't blow, but the boot didn't unlock (I did the double click with a slight pause between clicks)

I did a fast double click and the fuse stayed ok and all doors & boot unlocked - perfect?

Is is normal for the boot unlock to require a fast double click?

anyway, my main problem is solved, dunno how, other than drying out the loom & carpets under the passenger carpet (No corroded wires apparent though)

thanks for alll your help folks