2000 Honda Accord alternator

DEBBIEJ

MEMBER
2000 HONDA ACCORD
6 CYL
AWD
AUTOMATIC
70,000 MILES

I took my car to the dealer for an oil change and they did a check on the battery and said I need to replace it. I had replaced the battery about 3 yrs ago from sears and it was still under warranty so I went back to sears and the guy told me the battery was find but the alternator was low but he replaced the battery anyway. I then went to auto zone to get a free check of the battery and alternator and the battery was find and the alternator votlage was at 13.0 and the guy said this was ok. I have been reading and and it said voltage on an alternator should be between 13.5 and 14.5 I drive on the freeway everyday to go to work and don't want car to die out. Is voltage safe at 13.0 or should I have it replaced.

1 Reply

JUSTIN FREED

MEMBER
87 POSTS

Yes, 13 or so, maybe a bit above is probably good. The real issue is not the specific voltage (okay, if it was 10 or 11 there is probably an issue) but the relationship between the battery voltage when the car is NOT running (should be somewhere around 12 volts - again, that could be higher especially if it is a new battery) and the voltage at the battery when the car IS running. Naturally, when the car is running, the alternator should be putting "juice" into the battery.

A simple way to check this is to use a voltmeter. Read the DC voltage at the battery with the car shut off. Start the car and read again. It should be something like, 12 volts and then 13.4 volts. Or something like that. If it is 12.6 volts w/ car off and the 11.5 volts w/ car running, you have an alternator problem. By that, I mean if voltage is lower when car is running, you have a problem since the alternator is not putting out.

Be careful not to assume the issue is the alternator per se; it could easily be a loose wire, bad connection, broken wire, corrosion etc. Hope this helps!