MBMB

A Sylvania 2721 bulb won't go all the way in to the bottom of the socket in the defrost pod switch. When I push it in as far as it will go without forcing, it comes on with the ignition switch. Is this how it's supposed to behave, or should it come on only when the defroster is on, or when the headlights are on?

Thanks,
MB

dbd

Be extremely careful you don't mistakenly cause the bulb tangs in the switch to touch as you will melt the representative and associated ground wires.

I would make sure you have someone in position to disconnect the battery ground strap while testing.

Ed Scherer

On my '90 S4, it comes on dim with the head/parking lights, and bright when activated (independently of the head/parking lights in the latter case, IIRC).