driver door lock fault diagnosis

[Jimbo79]

Hi Everyone,

It seems like I'm having the common door lock issues on my Mk1 TDI 110 estate.

Things that don't work:

Remote lock/unlock doesn't work(works on all other doors).

Inside door handle doesn't work (feels like its not attached to anything).

Door LED doesn't flash when locked.

Manual locking of door very intermittent (feels worn??).

Things that do work:

Electric windows

Electric wing mirror

Opening/Closing of windows if you hold key in place when turning.

My main concerns are the interior door handle and manual locking of door not working. Would replacing the lock mechanism fix these issues? I've read the sticky about the door lock microswitch but I don't think its just that.

Any advice/suggestions would be most welcome.

Thanks

James

[STSKODA]

water in drivers door mulitplug/or knackered ccu

take it apart and examine connector - then dry and refit.

searching the forum will yield loads of info - it is expensive to fix if not caught early enough

[Jimbo79]

water in drivers door mulitplug/or knackered ccu

take it apart and examine connector - then dry and refit.

searching the forum will yield loads of info - it is expensive to fix if not caught early enough

Right, I've had the panel off. The interior cable had snapped so thats easy enough to fix.

As for the central locking, I looked at the multiplug and it looked pretty dry and ok to me. I had a look/listen with the panel off unlocking/locking and the lock did try a couple of times (very feebly) and then stopped trying.

I'm gonna get a new lock mechanism but will this mean I need new keys?

Thanks

[STSKODA]

don't get new lock mechanism - get it on vag com and scanned for faults

it'll be one of 3 things

either knackered electric window module (unlikely - if so replace)

split wiring loom (most likely, could be repaired or replaced - trace and check for continuity)

broken ccu ( very expensive and i think needs recoded at a vag garage)

[rwbaldwin]

don't get new lock mechanism - get it on vag com and scanned for faults

it'll be one of 3 things

either knackered electric window module (unlikely - if so replace)

split wiring loom (most likely, could be repaired or replaced - trace and check for continuity)

broken ccu ( very expensive and i think needs recoded at a vag garage)

Do the other doors lock/unlock when you use the switch on the driver's arm rest or the key in the boot/passenger side door?

If so, then it's not the CCU as all the door communications are working.

[rwbaldwin]

Have you checked fuses F10, F14, F37 and F38?

[Jimbo79]

Have you checked fuses F10, F14, F37 and F38?

No, I'll check those when I attack the wiring with a multimeter, from memory isn't the fuse box under the drivers side dash?

Thanks

[Jimbo79]

Do the other doors lock/unlock when you use the switch on the driver's arm rest or the key in the boot/passenger side door?

If so, then it's not the CCU as all the door communications are working.

Yep, all the other electrics work fine. Don't have access to VAG-COM so am gonna take a multimeter to the wiring loom and see where that gets me.

cheers

[rwbaldwin]

Yep, all the other electrics work fine. Don't have access to VAG-COM so am gonna take a multimeter to the wiring loom and see where that gets me.

cheers

That's good news as you've eliminated the most expensive bit (CCU).

First check the wiring where it passes from the 'A' pillar to the door. The wires are flexed everytime you open the door. The wires that fail most often are the thick Red/Yellow and Red/Brown wires which provide power to the door electronics. If you remove the lower trim on the 'A' pillar, it will reveal a set of connectors.

If it's not the wiring, then the next most likely cause is the control unit which is an integral part of the window motor. This controls the window, door lock, flashing LED, armrest controls, mirror control, mirror motors and mirror heating element. Unfortunately, the control unit is not available separately. The driver door lock control is usually the first to go.

[STSKODA]

ccu faults can be intermittent, mine had same faults and had new regulator, then loom, the finally ccu to sort it

however you are correct it is the most expensive bit, so the last one to try and change like i said

door loom is around £100 - think i have a second hand one kicking around if you want to try it

[Bowders1]

Right, I've had the panel off. The interior cable had snapped so thats easy enough to fix.

As for the central locking, I looked at the multiplug and it looked pretty dry and ok to me. I had a look/listen with the panel off unlocking/locking and the lock did try a couple of times (very feebly) and then stopped trying.

I'm gonna get a new lock mechanism but will this mean I need new keys?

Thanks

You will not need new keys if changing the door lock mechanism. You keep the original door handle and key lock.

I did a guide in the tech section to remove the door mechanism. Which sounds like you have read already:

http://briskoda.net/forums/topic/126257-octavia-1-replacing-door-latch-microswitch/

but i not convinced it will be your door lock mechanism with the symptons you have but could be wrong, possibly door control unit.

[Jimbo79]

ccu faults can be intermittent, mine had same faults and had new regulator, then loom, the finally ccu to sort it

however you are correct it is the most expensive bit, so the last one to try and change like i said

door loom is around £100 - think i have a second hand one kicking around if you want to try it

Thank you, I may well take you up on it. I'm gonna have a rummage with a multimeter first though...

[Jimbo79]

That's good news as you've eliminated the most expensive bit (CCU).

First check the wiring where it passes from the 'A' pillar to the door. The wires are flexed everytime you open the door. The wires that fail most often are the thick Red/Yellow and Red/Brown wires which provide power to the door electronics. If you remove the lower trim on the 'A' pillar, it will reveal a set of connectors.

If it's not the wiring, then the next most likely cause is the control unit which is an integral part of the window motor. This controls the window, door lock, flashing LED, armrest controls, mirror control, mirror motors and mirror heating element. Unfortunately, the control unit is not available separately. The driver door lock control is usually the first to go.

Ok, I've had a go with a multimeter where the multiplug goes into the window motor. Both the red/brown and red/yellow wires have 12v going thru them. I'm having difficulty getting the panel by the a pillar off but am presuming if I have power by the window motor, the connection there is sound. I guess my next step is the window control unit, but before I do that, I'd like to check that power is going to the door mechanism. Is there a way of getting the door mechanism multiplug off without removing the mechanism itself?

Thanks again.