Electrical Problems

[Kornstar56]

Hello,

 

I Am having big problems with my 2000 silverado with the 4.8 liter engine

 

Whenever I come to a stop the voltage gauge takes a drop and then goes back to normal. It just bounces from 15 to 14 volts on the gauge and whenever I go up an incline my battery light comes on. When this happens the motor almost stalls. I replaced the alternator and battery and it still does the same thing. I even took it to the local dealership and they checked all the connections and wiring but nothing was bad. I'm at my wits end with this vehicle. Any advice would be appreciated.

 

Thanks in advance.

[GM-Tech]

It just bounces from 15 to 14 volts on the gauge and whenever I go up an incline my battery light comes on. When this happens the motor almost stalls. 

 

Is the 14 volts you mention the low end when the voltage drops? If so, that is not an abnormal reading; however, the battery light should not come on at that voltage. It is a pretty simple system, though the problem doesn't sound like it's there all the time, so may be difficult to track down.

 

On your truck, the PCM (computer) controls the alternator AND the battery light in the cluster.

[Kornstar56]

Got back from the dealership and they think that the voltage regulator in the alternator because the even though the gauge was bouncing from 15 to 14 the alternator was only putting out a maximum of 13.6 volts and would drop to 12 according to their readings.

could the battery light be caused by overvoltage (bad regulator) because it only happens when you have to give it a little bit of gas. It was a remanufactured alternator I put in it so I wouldnt rule any thing out.