HornsManiac

I have bought 2 rebuilt alternators from the same parts store and put them on my 03 Accord EX 2.4L. Both times the alternator was showing 14.3 volts when I first put it on. Then within 30 minutes of use it was failing. Indicator lights started coming on and power started declining. When I got the car back home and checked it was at 7.5 volts. My first thought is I bought two bad alternators and that makes the most sense. However, before I just assume that I want to make sure there is nothing else that could be causing this problem. My battery and starter are both brand new so I don't think it is either of them. Thank you so much for your help! Blessings.

Kyle

poorman212

Have the battery tested and fully charged.

There is a load detection on the car and the PCM can and will cut the charge of the alt if it detects certain conditions. Long story on all of the conditions.

So I'm wondering if the PCM is "seeing" low battery voltage and cutting the alt output in an effort to save the from burning up....the alt is not designed to "charge" a low battery.

In short....pull that battery and alternator and have them both tested, what do the test results show?

HornsManiac

I bought the battery brand new yesterday morning, so I assumed it didn't need testing. Today I am going to buy an alternator from a different store and try that. Then if I am still having problems I will have the battery tested. If the battery tests good what do I do? How do I fix the problem of the PCM cutting the charge? Also, I have noticed the alternator itself gets really hot to the touch very quickly which makes me think it's bad. I am not 100% sure though. Is there anything that could cause the car to burn up new alternators almost immediately? Thanks.

Kyle

poorman212

Where are you testing the voltage?

I ask because if you are checking it at the battery and the car is running and you are reading 7.5V. With the car off, what is the voltage at the battery?

Anyway, I hope you took the battry with you when you went to the "different store" for another alt.

HornsManiac

Thanks to all who helped. The problem has been solved. There was a plastic wiring connection in front of the intake manifold on the driver's side that was not clipped together tight. It was not letting the alternator charge making me think it was bad. It was also setting off the CEL code for Knock Sensor. All is well now and the original alternator was never bad and is back on the car. The replacement one has been returned for a refund of my money.

Kyle