My 91 Integra battery wont charge and it isn’t getting electricity from the alternator. Yet when I had each of those things tested, both checked out just fine. I have checked all fuses, and now am out of ideas. Any help would be appreciated
How was the alternator tested? In the car at the battery posts or outside the vehicle in a bench testing machine? If you’re getting around 14 volts at the battery posts and the connections are clean and tight but your battery isn’t charging, your battery is bad. If you aren’t getting around 14 volts at the battery posts but the alternator passed a bench test, the wiring between the battery and the alternator is bad.
The alternator and the battery were both bench tested seperatley, and both passed. I figurd it was the wiring, but that is WAY beyond my expetiese to fix. I tried tracing the wires, and it combines with so many other wires that I got totally lost. Do any of you think a mechanc could fix this for less than this old POS is worth?
Make sure that the battery warning light turns on when you turn the key to the on position without starting the engine. On most systems current runs through the warning bulb and to the alternator field. If the light isn’t working the alternator won’t work.
Yeah, it turns on. In fact, my first warning that something was wrong was when the battery light came on. the second was when the lights started to dim. The third was when it died on the side of the road in the middle of the night 20 minutes later.
I had a 1990 Toyota pick-up with a similar problem. The alternator light would go on for several minutes, then off for several minutes. I had it go on for the entire trip home from work one day. Took the alternator in, and it bench-tested fine.
Turns out the brushes were completely worn out. When they would lose contact, the alternator stopped charging. Hit a bump to restore contact, and the alternator was fine. I just changed out the alternator, and all was good again.
How did you determine it was the brushes?
Took it apart. I decided I was going to replace it, so I let my curiosity take over.
Since the field lead of the alternator appears to be ok it would be good to see if the alternator has any output as the next check. Check the main output lead of the alternator with a voltmeter and see if you have more than 13 volts there with the engine running around 2000 RPM. You can also see if a screwdriver gets attracted to the alternator to check the magnetic field action. If there is a good voltage on the output lead there may be a bad fusible link that ties the alternator to the battery.
The alternator has a clip with 3 wires coming out, and I am not sure which one is the output lead. A screwdriver is not attracted to the alternator while it is running. Where would I even find a fusable link? I looked at the wiring diagram and I dont think it showed any fusable links, but honestly, I have no clue what I am doing here.
The large wire tied to the alternator is the output wire. It has to handle the high current generated to charge the battery. Check to see if there is 12 volts on the three leads on the back of the alternator while the engine is running.