hi guys - still looking for help here. I did the following test and saw 29.8 ACV using my multimeter. This below says anything greater than .5 is bad and points to bad diodes...could mine really be THIS bad? fyi, I tested at battery terminals and from back of alternator, same result.
- To check for a possible bad alternator diode, switch your voltmeter to a low setting on the AC (alternating current) voltage scale.
- With the engine running, touch the meter probes to the battery terminals—positive (red) meter probe to the battery positive terminal, and negative (black) meter probe to the battery negative terminal.
- If you find more than 0.5 ACV, it's likely the alternator's rectifier has one or more bad diodes.
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