Headlights affecting PM3

[GMills]

When headlights are turned on, PM3 fuel light goes out and/or starts to flicker, and truck bucks. Turn lights off and it smoothes out. It is wired according to instruction, all connections soldered. No codes are displayed. Any ideas?

 

[diesel4power]

Don't know how if its connected as instructed but it sounds like you are getting voltage drop due to the lights being on maybe then PM3 is not working right. You could make a simple setup where you connect the POS and NEG from the PM3 direct to the battery and then take it for a run and see if it eliminates the problem. Anyhow thats where I would start.



Paul

 

[GMills]

Well after having problems for 5 months the problem is solved. It looks like it was the alternator. Had the rectifier replaced and it works great now. Dodge had checked the alternator a onth or so ago and said it was fine. This weekend it packed itself in. I had a shop take it apart and the 4 diodes in the rectifier were shot.