Where is the voltage regulator on a 2004 Tahoe (4800ci)

[Vincent Mitchell]

I am replacing the Alternator for my vehicle I haven't removed anything under the hood yet, but Alternators are pretty straightforward. Can someone tell me where the voltage regulator is located in this model? Vin: 1GNEK13V14J117672 Is it built into the alternator?

i am about to put a meter on it to see what the readings are at the battery, I am pretty sure the alternator is going bad, but I want to rule out the regulator too.

 

[Fless]

The regulator is built into the alternator. According to your VIN you have the 145A alternator.

 

[Vincent Mitchell]

Awesome, thanks. I could not find a seperate regulator listed anywhere for this. I just bought an aftermarket Alternator that says it's rated for 250amps, so hopefully this resolves the flickering I am getting now.

Thanks so much for your input. I am not getting rid of this truck until it falls apart from rust.

 

[Donal]

I am replacing the Alternator for my vehicle I haven't removed anything under the hood yet, but Alternators are pretty straightforward. Can someone tell me where the voltage regulator is located in this model? Vin: 1GNEK13V14J117672 Is it built into the alternator?

i am about to put a meter on it to see what the readings are at the battery, I am pretty sure the alternator is going bad, but I want to rule out the regulator too.

The computer controls the alternator output voltage.

 

[Fless]

I think the voltage on this model year stays the same. Later, in 2005, GM introduced RVC for that.

 

[rockola1971]

I am replacing the Alternator for my vehicle I haven't removed anything under the hood yet, but Alternators are pretty straightforward. Can someone tell me where the voltage regulator is located in this model? Vin: 1GNEK13V14J117672 Is it built into the alternator?

i am about to put a meter on it to see what the readings are at the battery, I am pretty sure the alternator is going bad, but I want to rule out the regulator too.

Your voltage regulator controls alternator output voltage and current depending on engine RPM and vehicle power load (electrical consumption). As Fless has said, on your model year it is indeed in the alternator. I would check voltage output with headlights and a/c on at idle and around 2000rpm. You should be seeing 13.8-15.8v. Not many people service these alternators much anymore. It didnt use to be like that. Back in the 80's and before a regulator was $10 or less and an hour job start to finish and while you were in there you would replace brushes and diodes, but rebuilt alternators were less than $40 in the 80's for most common vehicles too. How they've trained us to spend more money......

In the 2005 model years they went to RVC where the field of the alternator was varied in accordance with power demand. It was essentially some engineer's pipe dream that if during non power demand periods the field duty cycle could be lowered which minutely lowered alternator drag on the engine which would in theory raise gas mileage. Not enough to be real world measurable. You would never see the difference from month to month of filling your tank.

 

[Tommy_Boy715]

The voltage regulator is not part of the alternator. Unplug the 4 pin wire going to your alternator, look at the wires and the 2nd wire in (depending on how you hold it to you) is a brown wire. That is you voltage regulator from the pcm

 

[rockola1971]

Charging circuit for Alternator attached. Voltage regulator is located in the alternator for 2004 Tahoe with a 4.8L. Brown wire is "Charge Indicator Control" which is the driver to your voltmeter in your instrument cluster.
RVC equipped vehicles have a 2 wire plug to the alternator with a terminal F and a L but the voltage regulator is still in the alternator of a RVC. There is an input from the PCM to the regulator to control setpoint and duty cycle via the 2 wire plug. If you unplug the RVC plug then alternator will revert to standard 13.2-13.8v charging because the voltage regulator is in the alternator.