Hello! I have a 2007 sedan octy. I have problems with towing electrics, rear demist and also the wiper motor. I've looked on fault codes and saw that it claims the rear demist is shorting. 

 

Could this all be linked to the cables being routed at the hinges to the rear "hatch"? Don't know the correct word for it (from Sweden).

Cables can break in the trunking at the hinge but likely to be a an open circuit rather than a short circuit. Easy to check.

 

Wiper motor failure is common on the hatchback (sedan). The screen wash fluid goes through the motor shaft and leaks can cause corrosion and electrical problems.  Replace.

 

 

I had similar symptoms when I purchased my 2007 Octavia. 

 

Remove the boot boot panel and have a look at both plugs. The main power cable which fed the rear dentist had melted the plug. Within the plug was all other wires for the boot and they had soothed up causing poor connections. 

 

I cut cut out the power wire and hardwired it and cleaned up all the connections and it’s all fine. 

Do you have access to VCDS? The towing electrics (if they are fully wired in) would show an error code as would the wiper motor. I've got wiring diagrams on my other laptop if VCDS doesnt help you. This will show you which plugs to test, from there you'll find the dodgy wire/plug

On 13/09/2019 at 10:42, GizmoThor8303 said:

Do you have access to VCDS? The towing electrics (if they are fully wired in) would show an error code as would the wiper motor. I've got wiring diagrams on my other laptop if VCDS doesnt help you. This will show you which plugs to test, from there you'll find the dodgy wire/plug

No but I have OBDEleven. Maybe that can show me the same codes?

I have OBDEleven and think it's brilliant!! Yes it would

Check in the spare wheel well and under the carpets on either side of the boot behind each of the rear light clusters for water ingress.