Help!

[Lex77]

My friend has a t5.1, 2011 and we have put in after market rear lights, which are LED's. We finally got them wired up and they were working fine, but now we are having problems! If we have the lights on (headlights) with the engine off, they are fine, however, when we start the engine the rear and front lights on the drivers side cut out! It's driving us mad! The lights on the left are all fine, only the drivers side cut out, can anyone offer me some advice please? Thank you so much!

 

[mmi]

If we have the lights on (headlights) with the engine off, they are fine,

Just to clarify - do you mean that ignition is on?

when we start the engine the rear and front lights on the drivers side cut

Just to clarify - all lights or just parking/side lights, headlight, indicators, brake light, reversing light?

Can you read fault codes?