I’ve got a 2003 s10 with the 4.3v6.
When I start the truck in from a “cold” start the alternator charges as should (about 14.5 volts). However if you start the engine after it warms up or is just hot in general the alternator will not engage (reads about 12 volts). The truck has never had an issue starting with this charging issue happening just no engagement from the alternator. We’ve tried two alternators and had them tested (came back good), we replaced the ECM/PCM, checked all grounds on the truck (all intact), even replaced the positive battery cable that had some corrosion in it as well as the instrument cluster. All fuses in the under hood fuse box check out good. I’ve exhausted all resources if anyone has any answers please help.
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