My defrost light is on.
 

1997 Boxster light in defrost switch is on...thought it might be the relay so I replaced it. Still on. Goes off after car is locked for 30 minutes or so. I assume that when you push the defrost button the relay is supposed to stay energized for 15 minutes or so and then turn itself off. As I have no rear defrost I assume that it's for the heated mirrors...Or am I wrong?

That is not normal operation. The side view mirrors do not operate with the key out of the ignition, or ignition off. When you energize the mirror heaters, they will stay on for 12 min. and then go off, but again only with the ignition ON.

Sounds like a new starter (ignition) switch could be in your near future.

:cheers:

I don't think it is the ignition because when car is locked eventually the light goes out. When I open the car with the key and the power locks open the doors, it comes back on. After the car is locked for awhile the light will go out. It is not the switch because I plugged the defrost plug into the power top switch and the light comes on in the same manner on the power top switch. I ordered a new relay and installed because I thought it might be stuck in the on position but no such luck..

fix found
 

This is what worked for me.

Two things to deal with:
One, take out the defective relay and check it for water (or rusty water). Mine was full of rusty water. Clean and dry relay socket area in general. Check for leaks (I didn't find one).

Two, fit new relay.

Mine has been fine for a month now, and, yes it has rained.

Cheers,

You do have rear defrost because all Boxsters came with rear defrost standard. This was done to accommodate the rear defrosters on the hardtops, which were an option from the introduction of the Boxsters.

If you look at the area where the driver's side roll bar meets the rear convertible top well, you will see the plug provided for the rear defroster.

Regards, Maurice.

he might be okay...it was a year ago

leak is the cause of relay failure
 

Back to square one: I thought I'd solved the relay side mirror/defrost problem by fitting a new relay, but after some torrential rain the problem returned. Removing the relay revealed it was full of water and shorting out. The root cause is therefore the water getting on to the relay.

I have scoured the posts on leaks, finding some evidence for a door seal or side-mirror related problem. I fully understand leaks like this require a methodical approach, but can anyone provide a systematic series of checks I can carry out?