ihave a 94 honda accord ex . i replaced the alternator but it still wont charge. checked all fuses , has a ground, output wire out of the ecm is 5.7 volts. have 12 volts at the alternator when key is on. i am lost please help . my wifes car and she wonts her ac back.

 

did you test the battery?what led to replacingthe alternator?

 

^ x2. Why did you replace the Alternator? Take the battery to an auto parts store such as AutoZone or Advance and have them test the battery. Also are the contacts at the battery clean an tight?

 

About that wire out of the ECU... Is that the "C" wire that controls the alternator? I thought it's either system voltage (13v) or the ECU grounds it to zero when the ECU wants to shut off the alternator.

If that wirehasan intermittent or partial connection to ground, the alternator might be interpreting that as a signal to shut down.