Over voltage

[zoom240]

My 260z's charging light came on & the votage indicator is showing high volts. When you rev the motor above idle, it jumps from 13 v to +16 -- off scale. The alternater & voltage regulator were replaced about a year ago & had no problems. The VR is a no-name brand (literally, no name on it). Got both from a guy at the Z club in Houston, so don't remember the origin, but they were new/refurbished.

So this week, I ordered a VR from British Victoria, but it's a Wells & it's got the wrong plug.

The odd thing is, when I unplug the VR, the voltage is rock steady. Isn't that odd? Any ideas?

Dave

[LanceM]

I'd say the VR is shot. I don't remember for sure but I think if you unplug the VR there is no output from the altenator, so the steady voltage you are seeing is the battery voltage.

[zoom240]

I suspected the voltage mtr wasn't reading correctly with the VR out. I've got to send the new British Victoria VR back, ... the plug is the wrong type. Will look around for a replacement.

Thanks

Dave

[TomoHawk]

the volt meter on my 280Z reads 16V with the engine on, a little less with the headlights on. I measured the voltage at the battery with the engine running and it reads a nice 13.5, so I will have to assume that there is a little something going on with the wiring somewhere else and the voltmeter is reading that.

Can you get a volts reading at the back of the voltmeter? It would tell you if it isn't reading right & should be replace/fixed.

[zoom240]

All, thanks for the advice. Haven't responded for a while because I have a hard time reading the site when my car's not working. It's a European 260Z & apparently it has a 240Z-style Voltage regulator, as the first VR had the wrong kind of plug.

At any rate, that didn't fix it. The car's voltage has been rock steady since I owned it. Now, it swings up to 16 v when you rev the engine. I pulled all the grounds, cleaned them & locked them down again. No change.

Guess next step is to follow Tomohawk's suggestion & try to get a Voltage reading at the back of the gauge to make sure it's not a guage problem. Seems a long shot.

Could it be a bad wire going to the Voltage Regulator? Dunno.

Thoughts?

[TomoHawk]

Corroded wires going TO the voltage regulator (sensor side) would probably

show a lower battery voltage, and the regulator would appropriately bump up the volts coming off the alternator. In that case, the things are working fine, just the resistance in the one wire is screwing things up.

I.E: try a fresh wire from (the alternator to the regulator's sensor), or whatever is right for your stuff.

Then let us know if that's the thing.

[Daniel]

I cant say for sure on 260's but on a 240 that problem is caused by a bad connector on the white wire where the vr attaches.If you jumper around it the problem goes away.If not repaired your battery can explode.