Sure, you can make any harness work anywhere you want, if you are able to rip it apart, check and trace each and every connection against wiring schematics, make the needed changes, as harnesses as well as color codes changed a lot during those years.Hi, is there a way to make a mustang 5.0 1990-93 engine harness a3m computer work with a 89 dash harness? Please let me know if there's anyway to make this work other than buying a whole 89 engine harness, thanks!
I know its been answered but im willing to tear apart the 93 engine harness to make it work with the 89 dash harness if its possible. Thanks for the answers.I think you have the answer here on the first post you started
https://www.stangnet.com/mustang-fo...to-5-0-with-1993-5-0-manual-donor-car.900595/
To answer that, we need to know which functions of the EFI are handled by the dash harness. As I recall, my 89 had the PCM Power Relay and PCM itself both mounted behind the RH kick panel. Seems like there was wiring under the driver's seat, Fuel Pump Relay comes to mid. That would be fed-through from the dash harness. Only other thing I can think of in the dash is the CEL, fed by the PCM. There were no other PCM connected functions, I don't think. I don't have '89 wiring diagrams, but DO have 1990; will take a look at them. I had a '93 Cobra, but forget, but think, the PCM Power Relay by then was in the Battery Junction Box, underhood.I know its been answered but im willing to tear apart the 93 engine harness to make it work with the 89 dash harness if its possible. Thanks for the answers.
To answer that, we need to know which functions of the EFI are handled by the dash harness. As I recall, my 89 had the PCM Power Relay and PCM itself both mounted behind the RH kick panel. Seems like there was wiring under the driver's seat, Fuel Pump Relay comes to mid. That would be fed-through from the dash harness. Only other thing I can think of in the dash is the CEL, fed by the PCM. There were no other PCM connected functions, I don't think. I don't have '89 wiring diagrams, but DO have 1990; will take a look at them. I had a '93 Cobra, but forget, but think, the PCM Power Relay by then was in the Battery Junction Box, underhood.
Schematic diagrams are good electrically, but they do not show connector locations within the vehicle. Most good wiring diagrams DO show the relative shapes of connectors, which does help some. impHi, thanks for the reply and the information. Diagrams of all these harnesses would be the best but I myself cannot find them.
I thought engine harness is stand-alone? Ford’s aftermarket swap harness is based off of the 93 harness. That harness m-12071-a50 is what I used to convert the Daddywagon. Ford used to sell the 93 harness itself as a swap harness I believe. I think your answer is yes. Shouldn’t be too hard. Maybe 1 connector of wires different between years. And as mentioned earlier move 1 or 2 relays. The dash or chassis wires don’t share much with the engine harness I think. VSS, A/C, Tach, KO power, ground, engine light, power in start & run? I wanna say connector by wiper motor but not positive.
Hey, no the 4cyl 89 is the dash harness and I'm converting it to 5.0 using 93 stuff. I'm keeping the 89 dash and going to cut up/modify whatever on the 93 5.0 engine harness to make it work with the 89 dash Harness since you said the 93 can be run stand alone.I am not sure what you mean by “rip apart the harness”. Is the 89 a 5.0? You shouldn’t have to rip it apart.
I am not sure what you mean by “rip apart the harness”. Is the 89 a 5.0? You shouldn’t have to rip it apart.[/QUOTE]
You "rip it apart" only to the extent that if connections as indicated in schematic diagrams do not match pin numbers on connectors, you must remedy that, so that all sensors and such are properly connected.
Working year-to-year has shown me that early in the '90s Ford began skipping wiring conductor colors around, as well as maybe conductor numbers. This means that an EFI harness off an '89 may have different connections than a later one. IN GENERAL, '89 to '93 are pretty alike, but no guarantees. '94 up definitely different.
If yer installing an EFI motor in an early car, for example, you had better have wiring diagrams relating EXACTLY to the EFI harness used, or exact wiring information relating to the engine, year, and model being hooked up. Horrible headaches can happen otherwise. (Been there). imp