When my truck is at idle, I've been noticing the Amp gauge drawing down BELOW 14 Volts in a cyclical pattern.

Meaning every (2) minutes or so, it will show a HIGH Amperage draw down (gauge moves left and the lights dim). It will stay in this draw down for about 15-20 seconds or so and then return to normal.

It's acting like heating element is cycling On-Off. There are NO gauge lights coming on and only the AMP gauge shows the suspect activity.

My truck no longer has the Fuel Pre-Heater element. It melted last year and removed it completely a few months ago. I also recently had the alternator, batteries checked out and terminals all cleaned. All checked out just fine.

What is causing this intermitten HIGH Amperage draw on my truck's electrical system ???

 

when you first start it ?. does it do it all the time ?,when warmed up ?.
Clark

 

It sounds like the grid heaters cycling on and off. This happens when it is cold outside and the truck is cold--right??

 

Grid heaters... make sure they only cycle when the air is cold and the engine is at or close to idle at less than ~16mph

 

grid heaters draw over 200amps,they should cycle until the truck warms up or hits 20 mph once.

 

I believe he said he took the grid heaters off???

 

He said he took the fuel heater off after it (the connecter, usually) melted.

 

Oh ok, misread I vote grid heater then!!

 

If the climate control is in one of the defrost modes the air conditioner will cycle on and off.

 

My old 99 did the same thing once it hit about 65000miles. It didn't matter what the outdoor temp, how warm the motor, what speed you were traveling, or what was on tv.......never could get the dang thing to stop. It would literally dim the lights it was so bad.......