External voltage regulator issues.....

A few years ago I had what I thought was a bad alternator, but even after testing that, the ECM, and the cam sensor, nothing resolved the issue and the truck wasn't charging. I installed an external voltage regulator and life was good for awhile....now it will randomly go from 14 volts to 18 while driving and the red warning light pops up on the dash......this will only last a few minutes and go away. I am positive it's actually not overcharging the batteries because a multi-meter shows 14 volts regardless of if the light is on or not.....sometimes it'll go a month and not do this, other times its 2-3 times a week. any help on this woud be appreciated....it's just kind of annoying.

I don’t see how adding a voltage regulator on top of what was already there would create voltage. Did you bypass or eliminate the existing regulator?

yes, it was bypassed, this was a last resort, I would of loved to actually solve the problem but even after trying to get it diagnosed at a dealershp they basically told me that even after swapping batteries, ECM, cam sensor, and alternator they were still unable to get it to charge correctly, so I decided to wire in an external one......

It's likely a cluster issue.
Or, worse, a chafed harness issue.

Mark.

Mark Nixon said:

It's likely a cluster issue.
Or, worse, a chafed harness issue.

Mark.

Click to expand...

I chased this issue (half assed) for years, resorted to external regulator, turned out to be chuffed harness right on the drivers inner fender. I found it when doing a frame/cab swap.

Gorms said:

I chased this issue (half assed) for years, resorted to external regulator, turned out to be chuffed harness right on the drivers inner fender. I found it when doing a frame/cab swap.

Click to expand...

Think back.
Did you ever have, or was there ever a tire blowout on that side?
I had a bad one a while back. It took out everything behind the tire and above it.

Mark.