So at idle with the charge light on what is the viltage reading at the battery cables at the battery?

Answered by saturntech9 (expert)
23,177 answers provided

12.8 ish. I don't remember exactly since I tested it a couple hours ago, but it was definitely good.

Here's a fun twist. I went back out to test the voltage at the battery and the alternator and took my wife to run the accelerator. Everything was testing fine, and I had her run it up to 3500 to test at elevated rpm. The light went out. It hasn't come on since. I took it to O'Reilly for a separate errand and had them check it. They said it tests fine, but the battery is a bit low (makes sense since it was completely drained from the bad alternator.

So, two questions. Would a low battery cause the light? I thought it only came on with a charging issue. If so, why would it have been extinguished as soon as the new alternator was in the entire way home, then come on when I started it again?

Response from jdflight
1 question asked

Are you sure you dont have a bad battery?A bad battery can skew the charging voltage.Also have you checked the battery cables to make sure there clean and tight?Have you checked the negative battery cable to ground using a ohms meter yet?

Answered by saturntech9 (expert)
23,177 answers provided

The battery test O'Reilly did yesterday said it was good, just a bit low. I'll deep charge it next week when I have access to a charger. I haven't personally checked the neg to ground. The cables are relatively clean and yes, tight.

Response from jdflight
1 question asked

I would check the negative battery to ground and also the case of the alternator to ground.

Answered by saturntech9 (expert)
23,177 answers provided