mandtandk

Ok, I'm a complete idiot when it comes to electrical stuff. I would like to do the voltage regulator bypass thingy. The instructions say to connect the ext. VR to an ignition switched source. Specificly, where does one find such a source?

Thanks in advance

M

infidel

It would help to know the year of your truck

nickg

next question is why do you want to do the external VR??

mandtandk

Oops. Of course. It's a '97 3/4T 4x4.

My GEN light has been coming on. I did a search, and the thoughts were that the system functioned better with this ext. regulator. I thought I would give it a try before I forked out $$$ for a new alternator.

Thanks again

M

Number47

its been a while but isn't the voltage reg in the computer?? i know it is on my wife's winter beater 92 dynasty

rebal

yup its on the fire wall behind air filter
but it might be time for a new alt. have it tested

torquefan

The ones in the PCM generally work well and rarely fail. Also, I would think you would tend to get trouble codes and warning lights with a bypass. It is something I'd only do as a last resort, if a new PCM wasn't available. Chances seem to be better that it is just worn out brushes or a rectifier problem on your alternator.

Welcome to the site.

nickg

Most places will test an alt for free...

mandtandk

Well, I had the ALT tested and it was bad. Due to a time problem, I went ahead and got a new one. Put it on last night and all appears well.

Thanks for the help

M

infidel

For future reference the voltage regulation portion of the PCM on 12 valves have been known to fail and a external regulator is a much cheaper way to go.
Works excellent and cost less than $20.
Here's instructions for a 1st gen but they are exactly the same for any PCM regulated vehicle
https://www.dieseltruckresource.com/...n&onlynewfaq=1

Won't fix a bad alternator though