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Electrical From scratch: alternator wiring

  • Thread starter Thread starter fox racer v2
  • Start date Start date Jun 23, 2025
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fox racer v2

Active Member
Jun 2, 2019
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Brooklyn
Jun 23, 2025
#1
  • Jun 23, 2025
  • #1
Ok folks, few months ago I bought a second fox (1991, formerly 4cyl) and even more recently started tearing it down. This car will get a terminator X kit, so to my knowledge I won’t need the OEM main harness or injector harness.

For slightly more background, the previous owner hid the dash harness in driver side fender, and in doing so, extended a bunch of wires and eliminated a bunch of electrical connectors hence this post. They’ve also added a 3g and removed the orange/black power wires entirely.

I’m just trying to get my head on straight directionally. So if anything below seems off, please correct me, I’d just like a sanity check on how I’m thinking/approaching.

1. Dash Harness: I’m almost certain previous owner didn’t mangle this harness, I believe all the wire tucking work was after this harness. It has an 8 pin black barrel connector (headlight harness connection), 2 pin blue barrel connector (also headlight harness), wiper motor/low brake fluid/hood light connectors, brown 8 pin barrel connector (main harness connection) and a few starter solenoid connections (see below) and I think a ground (1 ring terminal that has ‘teeth’ on the inside of the ring ties together two black wires - looks factory)

2. Headlight harness: has no alternator plugs and no starter solenoid ring terminal connections. The 8pin barrel connector seems untouched, but the 2 pin blue barrel connector has the LG/R (alternator) wire chopped/hard wired.

3. Main harness: all connections accounted for however, it was re-taped and loomed so it has the alternator plugs on this harness and has been butchered. The LG/R alternator wire was hardwired back down to the blue barrel connector of the headlight harness so that needed to be cut to remove the harness. It also has the the yellow wire from the alternator that goes to the starter solenoid ring terminal.

Since the dash harness seems to have escaped the knife, and I won’t be re-using the main harness, I think the only thing I’m missing is the alternator wiring in the headlight harness. In which case. I can uncut and recrimp, or just get a new headlight harness (OEM off eBay and rewire for 3G, or just get a Ron Francis replacement already wired for 3G)

From what I can gather on the starter solenoid I have:
- 1 yellow (37) split into four (787, 185, 37 and 38) still in car/dash harness
- 1 DG/W which I only recognize by the small metal fuse block which I think runs power doors/locks. Don’t recognize the wire color though. Still in car, dash harness
- 90* rubber elbow connector. Still in car, dash harness.
- 4ga alternator wire, removed for now
- 4ga starter wire, removed for now
- EEC relay/computer power I believe is removed with Main harness
- Alternator regulator wire. Should be headlight harness, not currently

All above ignores airbag/smog connections - those are still there it seems but not hooked up.

Do we think I’m on the right track here?
 
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