Car Battery/Alternator

[Wardie]

Hey, I just tested my car with a voltmeter and came up with this.
When the car was off it sat at 12.50v - 12.55v
When the car was on it sat at 12.17v
Rev'd to 2000 goes down to 12.14v
Car is on and headlights on 11.93v
Is this normal, also after I turned off the car it went from 12.38 up to 12.50 again after a minute.

Has a brand new alternator in it as well.

Should I leave it idle longer? Any ideas?

[Gregs///M]

Should be at least 13.2 volts with a working alternator. Make sure the excitation wire is energized on the alternator. The small wire.

[Wardie]

Fixed it, the battery light in the dash was out. Replaced it and it charges now.. Ugh stupid idiot light.

[mr ilia]

Should be at least 13.2 volts with a working alternator. Make sure the excitation wire is energized on the alternator. The small wire.

How do you do that?

[george graves]

Fixed it, the battery light in the dash was out. Replaced it and it charges now.. Ugh stupid idiot light.

Odd. The cluster is supposed to have a built in resistor that if the bulb burns out, your alternator will still charge.

[Gregs///M]

How do you do that?

That's done inside the cluster.

Odd. The cluster is supposed to have a built in resistor that if the bulb burns out, your alternator will still charge.

I think only the newer clusters have the resistor. I've heard of a few without the resistor and rely only on the bulb.

[StereoInstaller1]

That's done inside the cluster.


I think only the newer clusters have the resistor. I've heard of a few without the resistor and rely only on the bulb.

Truth. Somewhere around '85 they fixed that

[mr ilia]

That's done inside the cluster.

I only have 12.4v at the battery with engine running.
Any pointers as where to find this wire? or DIY?

[jlevie]

Truth. Somewhere around '85 they fixed that

Hmm, the only clusters I've seen that have the resistor were from 89 & later cars.