Towbar Electrics have a mind of their own

[Greegiecee]

Hi all, hope someone can help me.

I have a mk2 X reg) toledo TDi. It has had a towbar on forever which has been fine. It hasn't been used in a while. Last weekend I hooked up a Thule bike rack with a lighting board. I am 99.9% certain that the wiring is fine as it's virtually brand new. I get driving lights but when I turn on an indicator the lights and indicator alternate and a faint beep (like the lights on warning) comes on. Any ideas what this could be?

 

[m0rk]

Sounds like the wiring on is not right on one side.

Wouldn't be too hard to check the car side with a multimeter though?

 

[Muttley]

Indicator making the lights and indicator alternate is a classic symptom of bad earthing. Used to be seen a lot on cars (Vauxhalls ISTR) with poorly earthed rear light clusters. So I'd check the earth connections first.

 

[Greegiecee]

Thanks guys, I read somewhere that if it hasn't been used for a while it's a good idea to pull the "trailer" fuse in the fusebox next to the steering wheel. I did it and the lights work 100%. I still get the beeping though so will check the earth and see if there is an issue with that. Thanks for the advice.