Charging problems

Mark,

Check to see if there is +12 volts at the "A+" terminal of the voltage regulator. Try to measure at the tab on the regulator. This wire goes from the "A+" terminal to the battery post on the starter solenoid.

Verify that the wires and connections from the voltage regulator's "F" (field) terminal and the "S" (stator) terminal are clean and not broken. Check both ends of each wire. The copper wire has been known to have broken INSIDE of the insulation, which makes the break very difficult to find.

Try adding an extra ground to the voltage regulator's metal base.

If you are still using an ammeter, make sure that everything is ok there.

John

I had a similar problem, had 2 techs look at it to no avail. Finally sat down and examined the whole circuit, at the end it was a bad connection where the blade connectors fit in the alternator.

I've cleaned all the wire ends and grounds. Made a new ground from regulator base to Alt. case.

I have 12 volts to the regulator (blue wire) when it is not connected to the regulator. When I connect it to the regulator the voltage drops to 1.9 volts. I suspect this is the problem area Solutions?

Mark

When you measure voltage across the "I" terminal with the the blue wire from he discharge lamp connected, you are essentially measuring the voltage drop across the regulator to ground through the internal resistance of the relay within the unit.

You must check the voltage at the wire connected to terminal "A" on the regulator to verify you are getting battery there. With the engine running and a properly working regulator and alternator, the battery discharge indicator lamp in the dash will light up if it does not "see" the battery on terminal "A", which is connected to the positive terminal of the starter solenoid.

I've seen alternator/regulator wiring go "open" in the middle, as well as at the ends where the terminals and/or connectors are. Follow each heavy gauge wire from end to end, visually, or sliding your fingers along the wires. Look/feel for bulges in the insulation or burned spots on the insulation. If that doesn't work, then a wiring continuity check would be next.

I don't know how the ignition switch might fit into these symptoms, but it is a source of many problems.

The diagram below is a diagram specific to the Pantera's charging system.

Bill Taylor has a nice diagram representing the Pantera charging circuit as well as a description of it's operation. Go to the PanteraPlace.com and check it out.

http://www.panteraplace.com/El...TEM%20(PAGE%201).pdf

http://www.panteraplace.com/El...TEM%20(PAGE%202).pdf

Mark,

Try using a "momentary" jumper from the "A+" (or battery terminal at the starter solenoid) to the "F" (field) terminal. DO NOT make this connection for more than a few seconds, as this will (should) cause the alternator to produce max output.

You don't need to have a second person to help. Just start the engine and MOMENTARILY make the connection. You will hear the engine RPM drop as the alternator "loads" the engine.

Or, you can disconnect the wires at the "I" and "S" terminals, and connect a jumper wire from the regulator's "S" terminal to the "A+" (battery) terminal, as in the diagram below.

John