'84 Carrera faulty DME?

[Roger 911]

I have a '84 Carrera motor. Car has been sitting for about a month. Ran/started fine before it sat. Won't turn over now. Confirmed that when trying to start, there is no power being sent to either the starter solenoid, or the fuel pump. Swapped DME relay, no change. Originally thought it was faulty ignition switch, swapped that, no change. I'm thinking it might be the DME itself.

Any other suggestions?

Roger

[86 911 Targa]

Originally Posted by Roger 911

I have a '84 Carrera motor. Car has been sitting for about a month. Ran/started fine before it sat. Won't turn over now. Confirmed that when trying to start, there is no power being sent to either the starter solenoid, or the fuel pump. Swapped DME relay, no change. Originally thought it was faulty ignition switch, swapped that, no change. I'm thinking it might be the DME itself.

Any other suggestions?

Roger

Let's start with the "simple" stuff first.

1. Battery cranking voltage/amp check.

pm me as needed.

Gerry

[Quicksilver]

The DME doesn't power the starter solenoid so you have somewhere else to search. Obviously you need to have 12 volts from the battery cable at the starter but that would be hard to break.
I would start by checking at the starter switch to make sure it has voltage in and the starter circuit switches on when the key is turned.

[Roger 911]

I guess the fuel pump won't run if the starter isn't turning the engine over, since the DME needs to see RPMs before it will power the pump. So the real question is just why am I not getting power to the yellow wire that activates the starter solenoid? I know the solenoid works, because I powered it directly and it does work. Just no power getting to that yellow wire.

Roger

[Roger 911]

Originally Posted by Quicksilver

The DME doesn't power the starter solenoid so you have somewhere else to search. Obviously you need to have 12 volts from the battery cable at the starter but that would be hard to break.
I would start by checking at the starter switch to make sure it has voltage in and the starter circuit switches on when the key is turned.

OK. This is helpful. Thanks.

[86 911 Targa]

Originally Posted by Roger 911

OK. This is helpful. Thanks.

By The way, do you have the factory alarm?

Gerry

[Roger 911]

Problem solved! A fuse wasn't fully seated in the engine compartment. How silly.

Roger

[BER]

Roger,

Just curious - do you recall which fuse was the issue?

Thanks.

[Roger 911]

Originally Posted by BER

Roger,

Just curious - do you recall which fuse was the issue?

Thanks.

My chassis is a '72, so I'm not sure if the fuses are the same as on a '84-'89. Having said that, I think it was the top fuse of the three that are back there. However, I did wiggle/rotate all three.

Roger

[BER]

Ok. No worries.

I also have 3 fuses in the engine compartment, along with two large relays. According to my owners manual, the top fuse is a 25 amp fuse for the Rear Window Defogger/Rear Window Wiper Return. But like you said, my fuse layout may be different.

Anyway, glad you are running again!