So I am onto my third alternator now, the first was used and unknown condition, the second was brand new form an after market supplier, and the third is a Mazda re-man.

The first and second did not charge. I did not check the wiring previous to installing them. After seeing that either one did not charge I started following the trouble shooting manual in the FSM. They both did not have ANY voltage at terminal L with battery voltage at terminal S (with a jumper wire) and terminal B, regardless if the motor was running.

The third had voltage at terminal L with battery voltage at terminal S (with a jumper wire) and terminal B before I plugged in the wiring harness. After plugging in the wiring harness I went to confirm the voltages and then had NO voltage at terminal L. I reinstalled the jumper wire at terminal S and now saw that I had NO voltage at terminal L. With the jumper wire in place I started the engine and was measuring less than 12v at terminal B.

It appears that I have something wrong with the wire in the harness that hooks to terminal L but what could I have broken or tripped inside the alternator if there is either 12 v or ground (the two most extremes) applied to terminal L.

Ryan