mine runs like 16 volts all the time.?

 

Well on the volt gauge its maxed out, and the truck will act weird. If the fan speed is on 4 the gauge cluster works if its shut off the gauge cluster doesnt work.

All the post about external regulators were for older trucks. Will the external regulator work on a 2006?

 

I just got my pickup so I'm not sure about if I have an external reg. I just meant that mine seems higher than I would think normal. I noticed about a week ago when I would turn the lights on the voltage would drop way down and then shoot back to normal. It would do this for a bit and then go back to normal and stay there. I tightened the cables a little and it seemed to fix the problem for now

 

...cable...

 

What do you mean cable?

The size of wire between alternator and regulator?

Why is the cluster working and not working?

 

Before you go any farther-
Make sure your cables are in perfect shape... mainly the crossover cable. What side was tested? These things read one side but charge the other. Gives all sorts of goofy issues if your cables aren't in tip-top shape. Many times they go bad under the sheathing.
Common issue. Look it up.

Electrical system works well as designed. No need for additional external reg.

And to goldie88: working fine: grid heaters.