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mr_hyde 03-06-2013 06:44 PM

Strange Charging Issues
 
I'm having a charging issue with my track car. Here is some background about my setup:

'90 chassis running a 1.8 with an '04 MSM engine harness with Adaptronic standalone. I have an NA8 self regulating alternator with the white main wire and white/green and white/black wires in the 2 wire plug. Portions of the NA6 harness are being utilized for various things. There is a toggle switch for the ignition, a start button but the coils and injectors are powered separately from the 1.6 harness. The Adaptronic runs the fuel pump (circuit opening relay) by grounding the light green wire that runs around between the diagnostic box and old AFM.

The car has been in varying stages of construction over the winter and I was attempting to trim back some unused wires in the NA6 harness that were cluttering up the front of the engine compartment. These include plugs for the AC, headlight lids, horn, PS pressure switch and the extra fan I'm not using. Nothing appears to be shorted out.

When I got done, I didn't have voltage on the white/red wire at the circuit opening relay or anywhere else on the white/red bus for that matter. The BTN fuse is fine and the brake lights work. There were no blown fuses. After spending a bit of time looking for white/red wires that may have been cut, I decided to power the COR with the unused 15a airbag circuit in the cabin fuse box since it is 4" from the COR. That made the fuel pump happy and the car started fine.

Since the car was idling happy and there weren't blown fuses, sparks, smoke or flame, I didn't think much about the missing voltage in the white/red until I powered up the laptop and found the car's idling voltage at 11.x. The alternator wasn't charging.

The white/green wire at the alternator has voltage with or without the ignition on and with the negative battery terminal unhooked, there is no continuity between the white post and the chassis ground (no macro short circuits). It is my understanding that the white/black wire just goes to the idiot light in the cluster but there is no voltage there in either condition (with the 2-wire plug unplugged). I also took the alternator out and had it bench tested at the FLAPS and it passed with happy numbers.

My question (besides 'what is wrong with my car?') is what circuits, if any, would cause the alternator to not charge? Does the white/green wire give the alternator any instructions? Normal troubleshooting protocols would have me undo what I did right before this problem popped up but that isn't an option since many wires were cut. I'm sure there are details I have left out of this initial post so let me know what other information is needed. Thanks! :party:

mr_hyde 03-07-2013 12:25 PM

Resolved. In the previous attempt, I had a ground strap unhooked by the clutch master and a bundle of ground wires that were clustered in the OEM configuration at the passenger shock tower were cut individually. I bundled these back together and reattached the ground point and it charges now. I'm not sure which was the problem (perhaps both?) but I don't care.


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