I had hell with mine, 2001 TDI, started out the same, read the forums to check the Brake switch bought a replacement, fitted no better. then nothing on the tailgate worked. Check the wiring loom OSR but remove the boot totally, then pull the harness out as much as you can. Harness is about 12 wires more than half of mine were exposed or broken. Wife never told me the rear wiper did't work either. All rewired now but what a pain in the arse anyhow have a spare switch now