Intermittent electrics faults with my Superb

[adamjth]

Good morning,

 

I have a Skoda superb Estate Greenline 1.4 TDI  (Register in June 2014) which has developed a fault with central locking and the electric windows.  In more detail;-

 

- electric window control from inside the cabin is presently working from the driver seat but not the passenger.   Critically yesterday the reverse was true with the passenger side control working but not driver side

- central locking when operated from inside doesn't work.   when activated from key fob outside doesn't work either.  alarm can be turn on though

- previously i had the fault that all the driver and passenger off side doors would not open whilst the near side doors where fine.   this fault cleared itself.

 

please can someone advise what / where to faultfind?  this morning I expected all the fuses and they are fine.   I did read about looming faults but I am thinking this is more like a central fault as I don't understand why the electric window fault has switched as per my first comment?

 

thanks

 

Adam

[chimaera]

IIRC the master controller for door functions is in the driver's door, so any damage to the wiring harness in the driver's door is going to give trouble like you're seeing.

[adamjth]

1 hour ago, chimaera said:

IIRC the master controller for door functions is in the driver's door, so any damage to the wiring harness in the driver's door is going to give trouble like you're seeing.

thanks for your response....would that account for the fault switching between the doors for the electric windows?   i been looking at this 

 and the comment 'The lack of indicators, fixed with a battery reset is probably BCM (Body Control Module) or CECM (Central Electrics Control Module) related. Failures aren't unheard of, but are usually related to the retrofitting on HID / xenon headlight kits.'   i changed a headlamp bulb about 2 weeks (non xenon) before this issue occurred.    can't think how this would relate but. ...

Edited 4 May, 2020 by adamjth

[chimaera]

If you're having trouble with stuff in the doors, it's usually the driver's door wiring harness. Everything from the other doors routes back to that one via CANBUS. The only connection between the door module and the BCM apart from CANBUS and LINBUS is that it gets its power supply from it. If you have a multimeter, I'd suggest popping off the door card, unplugging the two ends of the wiring harness (A-pillar and door controller) and check wire-by-wire for continuity. You'll probably find a few cracked ones in there. Particularly the following three as they are the communication lines:

• A-pillar pin 7 to DCM pin 14, orange/brown
• A-pillar pin 8 to DCM pin 15, orange/black
• A-pillar pin 19 to DCM pin 10, green

[DEL80Y]

As posted above 

Take door card and get out the multimeter 

The wires can look ok on the outside but are broken inside insulation

another member replaced drivers control module and other parts ending up with an expensive bill because the wires "looked alright"
 

[adamjth]

Thanks @DEL80Y @chimaera tips on door panel I can find here https://www.instructables.com/id/ŠKODA-Superb-MK2-door-panel-removal/. what about replacing the wires if I found broken ones?  Where to order?

[chimaera]

A dealer is the best option, or you could probably get it online too. Over here at least, dealers are open for parts and servicing - so it would be worth a phonecall.

[DEL80Y]

13 hours ago, adamjth said:

Thanks @DEL80Y @chimaera tips on door panel I can find here https://www.instructables.com/id/ŠKODA-Superb-MK2-door-panel-removal/. what about replacing the wires if I found broken ones?  Where to order?

Am old school and Scottish so I cut old wiring out and replaced with same cable spec for each wire that I was replacing adding in about 3cm longer to stop it happening again.

I couldn't justify the expense of a new loom for 4 broken wires

Get an auto electrician to do it if you have to soldered before

shouldn't be more than an hours work even less if you have stripped door panel for him🤑

[silver1011]

Before removing the door card, it is easier to prise open the rubber gater in between the drivers door hinges.

 

Whilst it is true that the wires can break inside the insulation, it wouldn't harm to do the easy check before removing the door card...

 

 

 

If the wires look intact, then the door card removal is described in a little more detail here...

 

 

 

[adamjth]

thanks @DEL80Y and @silver1011 for tips.   I am fine with a soldering iron but more nervous about door panel removal and fitting it back without issue.

[silver1011]

Exactly, so whip off the rubber gaiter first, it's dead easy, and take a quick peek inside to see if you can see any obvious signs of damage...

[adamjth]

All just to confirm it was the door loom as pictured

[rover220]

27 minutes ago, adamjth said:

All just to confirm it was the door loom as pictured

 

have you repaired or replacing?

[drefaldwyn]

On 05/05/2020 at 11:56, silver1011 said:

Exactly, so whip off the rubber gaiter first, it's dead easy, and take a quick peek inside to see if you can see any obvious signs of damage...

I've had a quick look at the rubber gaiter on my car but still unsure about the best way to remove it. Seems to be stuck on at door end. Didn't want to use too much force as I want to avoid damaging it. Can you please clarify the best way to remove it? Thanks. 

[silver1011]

I've never needed to do it on my Superb, however I'm guessing the gaiter / bellow design will be similar across VAG?

 

Looking at this YouTube video it might be easier to start at the wing rather than door end of the bellow?

 

 

Good luck!