Starting to get cold here in the mornings....When she fires up...the volt gauge drops big time and the lights go dim for a few seconds and then back to normal...it will cycle a few times until it warms up..I assume it is the heating grid lighting up?? That sucker draws some serious juice!!

 

It sounds like your right, the heating grid operating. I remember watching the voltage drop for the first time after getting my truck and thinking "what's wrong?" untill I realized what was actually happening. Now I know it's just normal.

 

when yuo plug in, you will notice that the heater will kick on maybe 2-3 times and then run as normal, versus a cold start mine will continue cycling sometimes for the first half hour of driving. My best guess is that once your thermostat recognizes any temp increase it shuts off.

 

The grid heaters should only cycle for the first two minutes of operation. They shouldn't continue to do it for half an hour.

 

When I plug in. no matter how cold it is, my grids don't come on at all.

Actually 160 seconds is the max

 

ummm mine comes on even when plugged in

 

Thanks for straightening that out. I couldn't quite remember but knew that it was somewhere around there.

 

I've noticed my grid heaters come on when I turn the key on, but they don't cycle any more like they used to. Does anyone know what ohms the temp sensor in the intake should read at what temperature?

 

Sure they are really coming on or is it just the bulb test part of the starting sequence?

 

It comes on based on the air temp sensor not the block temperature.

 

FYI ~ Those grid heaters draw 220 amps under normal operation.