We had a mk5 golf in today so while my scope was setup i took some readings, It uses a perment earth and switched live, The scope was backprobed into the rear of the right rear tail lamp and the used the earth by the right rear lamp. A picture of the trace going from brakelight to sidelight: G5Stopt...
As a mk5 golf was to hand when I had my scope setup I took some readings for you. It uses a fixed earth by the rear lamp and switches the 12v supply. I used a back probe into the plug on the right rear lamp and used the earth point by the lamp, Here are the screen shots: Going from brake light to si...