Hi folks,, here's an update on my troubles..
Sorry about the length of post, but it may help others who run into just ONE of these problems.
With the Key turned on in the ignition switch, but car not started, battery dash light should be on. Once car is started, that light should go off. On Luigi, I see the exact opposite, with the battery dash light staying on indicating alternator is not charging. Put voltmeter on battery and it reads 11.75V and doesn't increase when the engine is turned on, which is also indicating alternator is not charging. I was trying to find out who made Luigi's 95A alternator and to determine the pinout on the VReg (in the enlarged pic above) to test whether its the VReg or alternator winding itself.
From the 3 pin pigtail connector, The yellow/white wire goes to B+ post of the alternator. The green/red wire goes to the dash light. The middle wire brown/white goes to the left connector - this seems to go to the common of the WYE winding of this alternator.
When the green/red wire is disconnected from the wire to the battery dash light, and the latter is touched to ground, the battery dash light turns on.....so battery dash light lamp is OK.
Then a friend told me the alternator pics look like its a ford alternator, and that one of the bolts on the VReg is labeled "ground here to test".
When you do that, BRIEFLY, you should feel the alternator surge. This is bypassing the VReg by essentially simulating the VReg telling the alternator that the battery is fully drained (by grounding the pin)....gimme juice!! Alternator DOES surge, and voltage at the battery terminal increases......so, this indicates alternator itself is OK....more on that in the conclusion.
I didn't like the look of one of the wires from the pigtail connector, so i removed connector and metered it out. 2 of 3 wires registered open circuit when wiggled. From the VReg pic you can see its a motorcraft make (Ford). From a local parts store they suggested its off a 1996 2.3L , Mazda B2300 truck or a Ford Ranger. They were right, found a new pigtail connector from Ford dealer.
Replaced the pigtail connector, turned on ignition switch, and then started car and the battery dash light behaved properly…dash light came on, then turned off and stayed off. Voltage at battery was going up and alternator was charging battery….I shut it down, did some other work around car, tried it again…PROBLEM RETURNED! The opposite of what I just saw re-occurred…dash light didn’t come on, and when the engine was started, dash light came on and stayed on, voltage unchanged at battery, alternator no longer charging AND…when I tried the “ground here to test” on the VReg, alternator DIDN’T surge this time, which meant NOW THE ALTERNATOR wasn’t working .!!
Removed alternator, removed VReg and exposed the rotor winding terminals. Cleaned terminals and found a cold solder joint on one of them. You can see in pic that the connection can be easily separated with a small blade screwdriver.
Re-soldered BOTH terminals, put everything back together and battery dash light and alternator now behaving properly……..don’t wish this on anyone….hope this helps someone on the forum!
Adham
