wicks

And the battery drain saga continues: Alternator was not the problem. Put new one in anyway, mine had a dying rear bearing and was showing significant oscillation of the fan.

This little switch was, and is, the problem, drawing about .200 of my .243 draw. Even after I replaced it with new. The switch gets battery direct power from the over-the-engine harness, which is connected to the starter motor circuit straight back to the battery. When I connect this switch, a spark flies and an extra roughly .200 amps draw kicks in. The other switches nearby are also all brand new and don't create any draw.

Does anyone know about this switch and the harness? What does it do, how and why would it be "closing" and sucking current and passing it into the engine block with the ignition off? Some other reason this switch could be creating the draw? Everything is in very good shape - it would be hard to imagine the harness has failed. It is impossible to wire it backwards, the connectors are large/small, so you can't mix them up.

Spyerx

what is the part number? Where is it on the car? is this a turbo only thing?

wicks

Part number 93061711800. Maybe a 930 and 964 turbo thing. It is discussed (I think) in this thread - something to do with telling the cold start injector how long to fire...that could all be wrong and not about this switch on my M64.50 plant.

https://rennlist.com/forums/911-turb...-critical.html

wicks

Is the thermo-time switch supposed make a loud "click" sound a moment after shutting off the engine?

Alex Sol

reading thru this 11 plus year old thread for first time. i've had the battery drain issues for a few years now. I purchased a ebay remote door lock module hoping to be able to lock / unlock the door without sticking in the key... it wouldn't arm the alarm which is fine. while working on it i screwed around with the passenger side door switch and lost the wire that goes into the front fender. I'm diggin into the wiring soon to see if i can find the battery drain source. i get 50 milliamps draw with the car off and alarm not armed... will try some of the many tricks the 964 braintrust has assembled.. did wicks ever find the problem and the 200 mA draw? and that goofy relay switching sound source?

wicks

You should get a magnet pen or some tape on a chopstick and get that door switch hooked back up.

Yes it was a short on the starter solenoid. Multiple methods but you can start with disconnecting various things and see when the current changes etc.

Alex Sol

@wicks..
ah, bloody short on starter solenoid! amazing the journey you went through to find and fix! congrats and thanks for sharing your findings!