• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Mustang/Centech Harness EFI Questions

dsmith01

Jr. Member
Joined
Dec 5, 2008
Messages
73
Okay, been trying to finish up the wiring and I have a few questions. Centech harness is installed and I've started reworking the Mustang harness.

I've created a common ground and wired the power circuits per Ryan's website. I do not know what to do with these wires.

Centech Harness:

IGN PWR
COIL+
Choke (I guess this can be removed)
Idle Sol
Dist Mod


Mustang Harness

Manual Transmission Signal Return (I have an auto...Remove?)
Low Oil (Remove?)
12v Start for TFI
NDS PIN 30
Ground for PIN 30 (Am I over thinking this one?)
Fuel ON (this is coming from the computer. Is it the switch PWR for the fuel relay?)


Also, I only have 2 coil wires coming from the harness but my coil has 4 connections on the pigtail.
 
OP
OP
D

dsmith01

Jr. Member
Joined
Dec 5, 2008
Messages
73
Got some help on a local forum (coloradoclassicbroncos.com). Between that and Ransil's link I think I have PIN 30 figured out. Thanks

I'm not real familiar with the centech labelling. Ign pwr and coil+ sound like the same thing to me. Tell me what they go to and I can figure out what the difference is. You'll need to use one of those to trigger the EFI relays.

Choke, idle solenoid and dist mod wires are not needed but might be useful in the future. Should be 12V in RUN. Either would also work to trigger the relays.

Remove the low oil wire. It works with the mustang instrument cluster not the ECM.

I would wire the pin #46/pin #30/NSS like the RJM harness with a pluggable jumper. For example, put a male connector on the pin #46 wire and female connectors on the pin #30 wire and another wire going to the "S" terminal of the starter solenoid. This would allow you to use either a manual or auto ECM by simply swapping the connector. Auto ECM connects pin #46 to "S", manual ECM connects it to pin #30.

What is fuel ON? Pin #22 in the ECM is a ground that turns on the fuel pump relay.

TFI START signal is pin #3 of TFI connector. It gets connected to "S" terminal of starter solenoid also.
 
Top