I have a 2001 2500 series Dodge Diesel Ram. Recently the check gauges light lite up on the instrument panel. I took truck in to the dealership and they replaced the powertrain module. Same voltage spike occurred while driving home. Returned and the dealership replaced the alternator.
Same voltage spike occurred. Now the dealership has replaced the battery.
The previous batteries were replaced last year.

Any suggestions...?

 

Clean and tighten all ground connections. Might take care of it, might not.

 

watching this one for sure, mine is doing the exact same thing

Randy

 

started a while ago

https://www.dieseltruckresource.com/...d.php?t=143043

 

I think I found the problem. A positive wire connection going from the left battery to the alternator circuit in the power control module was quite loose. Tightened it and the voltage spikes have stopped. Also the dome light is no longer flickering.
Thanks for the suggestions.

 

So, did the dealer refund the money spent on things you did not need? loose connections are the first thing a tech should look for!

 

HA HA HA you are one funny guy