voltage regulator

[exploder1221]

what exactly goes wrong with a faulty regulator, and when replacing one would i also have to replace the alternator?

 

[Dannyboy]

I just cut and pasted this from another thread of mine, hope it helps, all info can be found here

http://www.explorerforum.com/forums/showthread.php?t=216599


The alternator needs a signal from a hot wire from the ignition to signal it to charge. On the alternator there is a harness, in this harness there is a green/red stripe wire that I was able to tone back to the stock cluster.

Pictured below is the alternator harness. Using a toner or Ohm meter you can trace this wire to the dash.

On the factory cluster there is 2 plugs after I identified the green/red stripe I attached that to a "hot" wire when the ignition is on to turn on the voltage regulator. You can see the connection with a blue connector. Also note the red wire and green/red strip both happen to be the second wire in on opposite plugs. I left just enough slack behind just in case I needed to reconnect.

Upon connecting these wires with a meter on the battery the voltage immediately jumped from 11.9 to 14.5 when the truck was running. Problem solved. I also tested that this wire was only hot when the ignition was on. Sources tell me that if you feed the green/red stripe a constant power source with the ignition off you will drain your battery.

 

[Dannyboy]

so to help answer your question, the regulator is built into the alternator, test this with a meter, I give instructions how in my noted thread above.

 

[BrooklynBay]

The regulator is an electronic device which controls the amount of time the rotor is at full power. Check my thread on alternator rebuilding for more information. It's # 57 in my list of useful threads: http://www.explorerforum.com/forums/showthread.php?p=1722521#post1722521

 

[exploder1221]

thankyou both for the info