1985 DME/14 pin wiring to fusebox

SoCal70RSR · 03-30-2007, 10:40 AM

My notes aren't as good as I thought... Anyone out there with an '85 or close to that can double check
my wiring. The car is a '70 but all the wiring is from an '85 carrera.

Apparently my DME wiring consists of a thick red wire to the battery and three other wires.

1. Thick black
2. Red/Green
3. thin black

I'm not 100% sure how these connect. Could anyone be kind enough to double check their wiring and
post the info on this thread.

The other wiring comes from the engine bay through the tunnel. It consists of 9 wires.

1. gray
2. Gray/blk
3. blk/green
4. blk/white
5. green/yellow
6. gray/red
7. blk/red
8. red/white
9. red/blk

I've searched the archives for several days and have not found the answer. I've also checked
Marc's 2.7 to 3.2 conversion web site but either my wiring is different or I'm missing wires. My DME only has
one set of wires going to the fusebox. I've yet to find the black/purple wire to the tach ??? it's suppose
to come from the DME but for the life of me, all I can find are the wires on the first list along with the
power red wire.

Below is what I have so far and how its currently connected. Could someone double check my connections against
their running car? Thanks.

DW SD · 11:23 AM

Fernando,
Did you check this site:

http://www.addictionmotorsports.com/WiringHarness.htm
He did something a bit different. He made 14 pin connector adaptors, so he could leave the stock harness alone. On my two installs, I've moved the chassis 14 pin connector wires around to fit the engine.

I think one of those DME wires feeds the fuel pump 12V +. I actually hooked mine to an open fuse in the panel, so I could have a fuse for the fuel pump.

A second is switched 12Vs at the turn of the key. ***note there are several switched connectors in the panel. I had initially made the mistake of hooking the 12V+ to one that turns off when the car is cranking (the radio and probably headlights turn off while cranking). That doesn't help getting your car to start, while the DME turns off under cranking

Another is the tach feed. I think the little black wire may be the tach feed.

The third and I believe the red / green is the 12V continuous power.
Look for a wiring diagram for the 84 to 89 cars. 944s have similar DMEs, too, so you could probably find that wiring schematic and confirm that my recollections are correct.

***I can check my car tomorrow. I'm now thinking the red / green may feed the fuel pump 12V +. Sorry, my memory sux.

Doug

DW SD · 03-30-2007, 11:13 AM

I may suggest you use a rubber isolator to mount the lower right corner of the fuse panel, too. It would require another hole through the sheet metal, but is worth the support of the panel. You'd hate to have the panel move around and short to ground somehow.

I used the small Porsche factory isolater with the M6 threads. Put a nyloc nut on both sides. These are the same isolators you removed from the intake manifold and are found in the engine bay (for mounting the relay panel, etc.)

Doug

SoCal70RSR · 03-30-2007, 12:46 PM

Yes, please if you don't mind take a quick look at your car and let me know how your DME wires are connected.

For some reason the Bentley manual I have doesn't really follow the DME connections or tunnel wiring to the fuse box very well.

I just got back from running around town looking for someone that could weld an aluminum bracket to the side of my front cooler. It turns out the first shop couldn't do it and the second shop could do it but the guy went home already... arrrrggghhhh

Good point on the rubber isolator. I wasn't sure if I should drill the side of the wheel well panel, but I just might have to....

Anyone else with an '85 that could help out?

DW SD · 03-30-2007, 12:51 PM

You can send the cooler to Ben McFarland. Also, check out craig's list.
There are plenty of welder's in there.

I'll look at the wiring tomorrow.
We can talk on Sunday or possibly tomorrow.

Doug

SoCal70RSR · 04-03-2007, 09:49 AM

Bump

Anyone else out there with a similar wiring to an '85? If someone could take a peak to at their DME wiring and tunnel wiring to the fusebox for an 84 - 89, it would be much appreciated.

Lorenfb · 04-03-2007, 10:20 AM

"Anyone else out there with a similar wiring to an '85? "

It's very simple to hookup the key power inputs:

1. The DME relay pin 86 gets its power from the ignition switch.
2. The DME relay pin 30 gets its power directly from the battery.
3. The DME relay provides power to pins 18 & 35.
4. The grounds are pins 5 & 17.

These should be verified by using an ohmmeter.

That's it!

The only other pins that connect to the front are pins 21 (tach)
and pin 11 (upshift to tach) which MUST NOT be connected to
any +12 source, i.e. Pin 11 connected to +12 will destroy the DME ECM.

DW SD · 04-05-2007, 08:22 AM

Fernando,
Look for the pins to which Loren refered on the plastic connector block to the (where the harness you have labeled DME wiring exits the computer or DME relay).

In your above photo, I wonder if the thin black wire may have the purple stripe, which would indicate the tach lead?

Were I to venture a guess, I'd guess that pin 30 is tied to the large Red / Green wire and that the black wire would be tied to pin 86.

Your continuity meter will verify.

In my case, I chose not to run the upshift light, but I made sure it neither grounded itself, nor touched a 12V source. I cut them off the connector and heat shrunk the end to be sure.

Doug

Lorenfb · 04-05-2007, 08:35 AM

"but I made sure it neither grounded itself, nor touched a 12V source. I cut them off the connector and heat shrunk the end to be sure."

Right on!

yel911 · yel911's Garage

I am about to do a 3.2 conversion and ALL the answers were not on Mark's web-site. Here is a helpful link for the wires that go to the trunk.
http://www.claassen.net/mystery/

Moe,

DW SD · 04-05-2007, 10:11 AM

Fernando,
Marc's web page here, also has some info about the wiring:

http://www.pelicanparts.com/MotorCity/marcesq1/Modifications.html

SoCal70RSR · 04-05-2007, 10:27 AM

I talked with Doug on the phone yesterday evening and as he explained, the 9 wire tunnel harness provides lighting to the rear of the car,
blinkers, parking lights, etc. For some reason, I was under the impression they were DME related.

The good news is that I connected the battery for the first time yesterday and I have quite a bit of the lighting working. Headlights, blinkers,
windshield wipers, hazards, backup lights and the horn.

Still not working are the power windows on either side and the brake lights.

Moe, how far along your 3.2 install are you? I'm at the tail-end of my install of a 3.2 onto a '70, if there's anything I can help with, please
let me know. One quick question, does your DME wiring consist of 2 wiring looms to the front of the car? Have you found the black/violet wire? It looks
like I may be missing some DME wiring because I only have 4 DME wires total, a red to battery, one black (thick), one black (thin) and a red and green wire.

yel911 · yel911's Garage

I have my harness (engine to interior w/grommet) installed and I'm ready to install the motor/transmission. I figured, I'd get the mechanical done first (after installing the harness-to-interior). My friend Tim, said that he re-routed the engine harness (the harness from the alternator etc.) so that it could reach my factory located 14 pin connector. I made an adapter for back-dating my heat. (another friend, Dean, gave me the left side duct from a 2.7) so I'll remove my blower motor etc. All I'll need to do is wire the trunk area, like your doing, and fab a coil/feul filter bracket.