BlissfullyAly

I have a 2004 – 3.9L V6 Automatic
Whenever the charging system is tested both with and without a load, the voltage regulator comes up as failed.
February – installed new batter w/new terminal connectors (only 6 months old)
1 week ago battery light occasionally comes on
Test Batter – Bad Battery – Warrantied out battery

Later the next morning battery light comes on again
Test battery – Good & Fully Charged
Test Charging System – Voltage Regulator Failed
Installed new alternator
2 days later - everytime I hit 3k RPMs accelerating the battery light comes on and engine feels like its stripping. Test the voltages – it holds at 12V – Rev the car up to 3k rpms and it immediately jumps to 16V
Test Battery – Fully Charged Good Battery
Test new Alternator – Voltage Regulator Failed
Warrantied out Alternator
put on new pigtail connector since the wire was slightly split
put on new serpentine belt – was looking cracked and weathered
Immediately test battery after new alternator – Tests good – fully charged
Test new Alternator – Still Voltage Regulator Failed

Ground wires all look good and intact – removed conduit on main wire running down to starter and don’t see broken or damaged wires – don’t see any missing bearings or bearing issues on tensioner pully casing the belt not to spin properly
ALL ALTERNATORS EVEN MY OLD ONE BENCH TESTED GOOD
I’ve been driving on the newest alternator for 3 days now and I notice the car idle drop slightly trying to stall out and recovers, acceleration is fine now – currently not repeating 3k rpm issue.
All proper lights light up when in start position – no bulbs are out – so the no dummy light isn’t the issue.

Any ideas what else I can do or check?

jwog666

aftermarket alternators have a insanely high failure rate, its more than likely that that is what is happening. get an oe alternator, or keep putting on the free replacements till you get a good one. the longest streak of aftermarket alternators i changed before getting a good one was 7

Daehawk

Dont bother with those used alternators. Take it to a real alternator shop. I had problems and my alt kept testing good. Nothing wrong. Kept having problems. Took it to a 60 something year old guy at the alt place where he has worked since high school and he found bad diodes and replaced the brushes...basically he rebuilt it himself. Never had another problem..that was 5 years ago. Those shops usually sell alts too. Mine was larger than the stock one. i always try to get a larger alt.

BlissfullyAly

Thank you... I appreciate the replies... I thought 3 alternators was a high number to go through, with them all bench testing as good, no way I have 3 bad ones in a row, and started thinking at this point that there has to be something else electrical going on. Apparently 3 in a row is a small number.