Power to the DME?

[GreigM]

I'm trying to add a datalogger to the car and need to power it somewhere close to the DME - preferrably the same 12V source which powers the DME, but I can't figure out from the wiring diagrams of the DME where it gets its power...so can anyone tell me the color of wire (or pin#) that gives a 12V to the DME?

Alternatively is there a switched 12V close to that area of the car (the GT3 is effectively the same as a 996 when it comes to the wiring and DME)..its a year 2000 (pre e-gas).

Thanks...

[Loren]

Do you want power at the DME or at the front center console?

Front center console is easy - use the phone connector.

[GreigM]

Basically I need a 12V supply as close to the DME as possible - from looking at the diagrams I do have it would appear that the DME takes a 5V feed, so thats no use to me. The feed needs to be switched and not go to ground when the car is cranked....any ideas on a candidate source?

On a similar note do you know if the cigarette lighter goes to ground when cranked on a MY2000 - I know it is ignition switched, but unsure if it goes to ground and the car is in approx 2000 pieces just now, so can't test this.

Edited February 12, 2006 by GreigM

[Loren]

If your car has this a secondary air pump... look at the maxi fuse on the relay support next to the DME. It is for the secondary air pump - I don't know if it is hot all the time but it should be easy to tap off of if it is.

Or... look at the relay for the engine compartment blower fan (position 8 in the relay support). Pin 3 a Red/Black wire should have 12 volts all the time.

[GreigM]

Thanks Loren, will try that just now....

[GreigM]

Unfortunately doesn't look like it - the red/black seems to be 0 at all times (probably because engine is cold and blower is not needed yet?)

While poking around with my multimeter in that relay support, there is a relay in position 7 which has a thick red/green wire - on my diagram this is called a "START LOCK". That rd/gn wire seems to go to 12 and stay round about there (dips to 10) when the car is cranked, then if I shut down the car seems to stay around 12V for a while - any idea what this is and will it stay at 12V while the car is running, or is it something used simply for starting the car?

[Loren]

Try the Red/Green wire on relay 1 MFI-DI pin 3. That should be at 12 volts whenever the car is running.

[GreigM]

Loren,

Thanks, my assumption above was wrong, the red/green I was looking at was the one in position 1 - and it seems to give the signal I was looking for. I'll try wiring that tomorrow.

Thanks,

Greig..