2002 Ford Ranger alternator wiring

DAVEERVING

MEMBER
2002 FORD RANGER

Electrical problem
2002 Ford Ranger 6 cyl Two Wheel Drive Automatic

I got a new battery, then went to the shop and had the alternator tested. The test told me it was a wire problem. How do I figure out which wire I need to replace, and then how do I replace it. I have good (not great) mechanical skills. I have a few ideas, I would just like a few suggestions from professionals. Thank you for your time, any suggestions will be helpful. Thanks again

1 Reply

BMRFIXIT

MECHANIC
19,053 POSTS

TEST B: WARNING INDICATOR IS ON WITH ENGINE RUNNING, SYSTEM IS NOT CHARGING
1.Measure voltage between ground and generator terminal B+ (Black/Orange wire).
.If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Orange wire between generator and battery junction box. See WIRING DIAGRAMS .
2.Disconnect generator 3-pin harness connector. Measure voltage between ground and generator harness connector terminal "A" (Yellow/White wire).
If battery voltage is present, go to next step. If battery voltage is not present, repair circuit between battery and generator.
3.Turn ignition on. Measure voltage between ground and generator harness connector terminal "I" (Light Green/Red wire). If voltage is equal to battery voltage, go to next step. If voltage is not equal to battery voltage, repair open in Light Green/Red wire between generator connector and instrument cluster.

4.Connect generator 3-pin harness connector. Start engine and let idle. Measure voltage between positive battery terminal and generator terminal B+ (Black/Orange wire). If voltage drop is less than 0.5 volt, replace generator. If voltage drop is 0.5 volt or more, repair circuit between generator and battery