J_M

My 2000 996 developed a problem. Stopped at the gas station, filled her up and tried to start, nothing happened. All dash lights were the. Locked up doors, went in and now all power seems to be gone, no dash lights, windows don't work etc. Headlights are dimmed. Radio works. Key battery is OK so immobilizer is OK I think ...

Replaced ignition key lock, electrical part. All fuses looks to be OK. All ideas to what to check next are welcome ...

wildbilly32

Battery?

dporto

Be sure to check grounding points for Y cable - especially if battery checks out ok (clean/check terminals as well). The ground points for the Y cable are notorious for electrical problems (they become loose/oxidized and lead to all types of electrical gremlins).

J_M

Tried with my trucks battery and jumper cables, no effect ...
Interior lights are on

J_M

If I take ignition lock out and turn it with a flat head while having key in lock should the ignition come on ?

DBJoe996

Sure sounds like a dead battery. Did you use the jumper points in the engine bay? The reason I'm asking is your battery may have a dead cell, creating a situation where a complete circuit through the battery is not made. AGM batteries are notorious for working one day and completely dead the next. As said, make sure to check your engine ground cable behind the passenger side rear wheel. Also, it might work to take the electrical switch out and with the key in the ignition, turn it with a flat blade screwdriver....never tried that before myself.

J_M

Used jumper points and replaced battery with my trucks working one and tried that flat head trick. No effect. Spooky ...

DBJoe996

Did you replace the electrical portion of the ignition switch? Sounds like you are going to have to get at it with a multimeter to find out where the drop in voltage is going, or not going. Like with the truck battery connected, are you getting 12V to the engine bay jumper point? Check the ground continuity from the engine to the frame. Is it that you have 12V at the battery, 12V at the jumper point and nothing still happens when you try to start? How bright are the headlights with the different battery connected?

dporto

Jump points are after the ground point(s)...It's a long cable run from the front of the car (lots of resistance) make sure the grounds are clean and tight then try it again...

J_M

Thanks for tips, will check them out later today. I'll keep you posted.

DBJoe996

I'm not totally sure what the Start/Lock relay does, but it might be worth it to swap one of the spoiler relays for that and see what happens. Relay Support 2 is under the carpeting on the rear shelf.

J_M

Switched relays, no help. Grounding OK, brand new battery installed. 12 Volts at jump terminals, no volts on ignition lock wiring ...
Edit: Immobilizer issue of some kind ?

DBJoe996

Have you checked any and all fuses for the ignition, DME and immobilizer? What about the ignition switch electrical portion? I forget what is in Relay support 1, I'll have to look that up.

Ahsai

If stick shift, try jump the clutch start interlock switch. Otherwise, try another key.

speed rII

Immobilizer cuts only starter motor. All other electronics work. Check the battery voltage from battery and then at the engine, there is positive terminal above the ac compressor.
I bet that the fault is in the main power harness.