I've been promising to check my mate's Seat Leon (52-plate) for error codes for a while (I've got VAG COM 409-1 and a cheapie cable), so tried to do so when they popped round at the weekend.

Oddly couldn't find his engine controller, but didn't get long to look as his missus ordered me out of the car as she was late for shopping.

Anyway, he's just called up to say that since the weekend, the interior light's been acting up and wondered if I'd changed anything.

Seems like the "work when the doors are open" switch setting is behaving like the "always on" position - i.e. the interior light stays on, even when he's out of the car and it's locked and he's had to switch it to the "off" position to stop it draining the battery.

I wouldn't have thought that VAG COM could change the operation of the interior light. Any thoughts?

I wouldn't think it was conected.

He was confusing the light switch positions.

Doh!