I know this is an old thread however maybe someone can solve an annoying problem I have. I have a VW Polo SDI I'm trying to repair for an old lady. I don't think you guys have SDI engines it's basically a TDI without a turbo. Anyway I have no comms with the ECU and no flow plugs working. I want to install a glow plug relay to do the job automatically but I'm not sure which wire from the CTS I should connect to the relay. Anyone know? Apologies for the long post and thanks.