You have already replaced the battery which was great, you don't have that to worry about. So unless the alternator is no good the field wires must be tested, use your voltmeter to check the fuses in the power distribution center, and in the fuse block inside. You may find a fuse out that would possibly have an effect on either the PCM's field control or the power for a wire that is used for the TCM also. After you test these fuses like the instructions tell you here under checking fuses(important to know if you have 12 volts at the fuse, not just whether the fuse is ok or not) you can try full fielding the green wire coming off the field terminal at both the alternator and at the battery power harness to engine connector. With it on, the green with orange wire should have battery voltage, the green with no tracer(solid dark green) is the wire going back to the PCM, the engine computer, if after grounding that wire you have a full field the voltage at the battery will keep rising all the way up, so be careful not to full field it for more then a few seconds. The output wire from the alternator(largest wire) has a fuse in it also. A fusible link. It is rare but if the old alternator had a short in the solid green field wire somewhere, the alternator may have burnt that fuse link and shut all output off. Check that wire for having 12 volts at the back of the alt. And at the battery also. You'll find this link near the battery. It is a 10 gauge(thick) wire and colored dark green. The alternator output wire is the thickest wire behind the alt, usually red it may be black with a gray tracer on certain 97 engines. Check this link for continuity. Remember fuses first, both fuse locations. If you need help let me know. Good luck. You can full field it by grounding the alt. Solid green wire by probing the harness to engine connector(10 wire or 12 wire connector) on the battery side and jumping that probe wire to the negative terminal to see if the alternator puts out. OK. The green with orange wire behind the alt. Gets its 12 violts from the auto shutdown relay. The power center lid has identification for every relay and fuse in the box.
Friday, March 26th, 2010 AT 10:55 PM