My Gen lite is lit and the annoying buzzer is on at idle, even when the system shows 14 or 15V. Rev it up and the lite and buzzer fade out, but come right back as the engine slows. The battery is a little over 2 yrs old, and shows 13V with the engine off. I wonder if that's possible, if my meter is off a little. Anyway, the above condition is with a rebuilt alternator, a new regulator from Fusick, the expensive one, $123. The readings are the same when taken at the battery, the pos post on the alternator, or two of the four connections at the regulator. Also, there's a red wire with a black connection that I don't remember unplugging, it doesn't reach anything, does anyone know what it's for? I will attach a picture of it. Thanks to all of you, who are so generous with your advice.

 

Where is the buzzing noise coming from? You should not get 15v out of the regulator.

 

I suspect that the buzzing noise is the regulator malfunctioning.

Time to follow the troubleshooting guide in the Chassis Service Manual.

- Eric

 

The buzzer is a warning buzzer, probably the same one that's supposed to sound when you open the door with the ignition key still in. I wonder if the battery is bad, it was drained down to nothing a month ago when I left the map light by the radio on. I had all similar results with the previous alternator, which wasn't very old, and the previous and a new regulator. With my luck, it could be something as simple as a bad cell in the battery, but then again, it reads 13 V all by itself. Hmm. I'm wondering if I have a bad wire somewhere. I went through the flow chart in the service manual, and the readings are normal. I will remove the battery and go back to where I bought it and have them test it. Maybe it's that simple. If anyone has any other ideas, I appreciate it. Does anyone recognize that wire in the picture above? It seems unusual to have a wire not plugged in anywhere. Thanks.

 

If your meter is accurate it shows the battery at just over a full charge. What is the voltage at the battery when the engine is running at idle and say 2500 rpm? Can you post a picture of the item that's buzzing? Have you cleaned your battery cable lug and post connection joints making sure they are shiny and tight? Have you cleaned the terminals on the VR and connector? Have you made sure the bulkhead connectors under the brake power booster are clean and tight?

I have no clue as to the wire your referencing and my suggestion is to follow it back to where it comes from.

 

Turns out the buzzer sound IS the voltage regulator. New battery today and nothing changed. I'm gonna have to go over every connection and if it's not that, then I have a bad wire somewhere. Oy vey.

 

Make sure all of your grounds are good.

You'll get it.

- Eric

 

It turns out that it was staring me in the face the whole time. That extra wire in the picture above does go to the horn relay. I stuck a mirror and flashlight under there and there was the connection. I cleaned it and plugged it in and my problem is gone. Always the simple things first. I knew that wire had to go somewhere! What gets me is how did it become disconnected in the first place? I don't remember unplugging it, and it's nice and tight in there now. Oh well. Thank you very much to all who replied.