Hi. Honda Accord EX 2.3 liter , original Denso 80 amp alternator. Battery went dead stranding me on side of road. AAA towed the car. I tested alternator and it wasn't putting out at all. Diodes tested the same in both directions.
Purchased a new Astou alternator from Amazon. Tested the diodes. They tested higher resistance in one direction than in the other direction, but NOT INFINITE ohms of resistance in one direction. When I hooked the new alternator up, it was charging at 14.77 volts initially. My car battery was at 10.44 volts the next day. Should the diodes read infinite resistance in one direction? Could my battery be discharging overnight through my alternator? If I allow Autozone to test my alternator will my alternator test bad? THE CAR WILL RUN ON THE ALTERNATOR with the negative cable disconnected, but with the cables connected I get an AC reading of at least 22 volts across the battery terminals? What are your recommendations? I do have a good Fluke Multimeter.
Dennis-
Car is 2001 Honda Accord 4 cylinder 2.3 liter engine with 97,000 miles. Have owned car for many years without issues until now.
Since you have a Fluke multimeter, this is how that company says to check diodes:
https://www.fluke.com/en/learn/blog/digital-multimeters/how-to-test-diodes
This video may be helpful as well, shows how to check for current draining back through the alternator:
https://www.youtube.com/watch?v=aF7ml6Rr-Yg
You should also have your battery tested.
Autozone indicates there should never be more that .5 volts of AC across the battery terminals, and I'm reading at least 22 volts AC at all times. They indicate that this can cause the battery to boil and destroy it. Any thoughts on this would be appreciated. Thanks.
If that's the case the alternator must be defective.
DO NOT buy important parts on Amazon or Ebay. Get them from your local store and test them before you leave. The stuff online from these outfits is a lot of bogus, Chinese junk. So much for the thrill of the discount.
