UK-POLOS.NET - THE VW Polo Forum

Hello, I’m having an issue with my polo. Whenever I use my indicator and press the brake peddle, my passenger rear lights mess up. When this happens the reverse light starts flashing and not the indicator light. I knew something was wrong when the ticking indicator noise from within the cabin goes twice the speed than normal. It also flashes between the brake light and indicator when I’m not pressing the brake peddle. Please help me turn left again!!!

Check the rear lightclusters for corrosion, the models released between 2002 and 2007 have this issue, from MY2008 they did a fix for this.
My 2007 had the "aquarium" rear light problem and my 2008 didn't.

You could also check the earth wires (brown) for oxidation of maybe not secured good enough

yeah sounds like a grounding issue to me