I know several people have asked about grid heater times and when it starts... Well here you go...

GRID HEATERS

Above 59*F ........................ 0 Seconds ............................ No Post Heating

15*F to 59*F ...................... 10 Seconds .......................... Post Heating

0*F to 15*F ........................ 15 Seconds ......................... Post Heating

Below 0*F ........................... 30 Seconds ......................... Post Heating

Remember block heaters tend to offset the intake air temp so be aware that block heater will do this.

Also be aware that there is 2 grid heaters and during the pre-heating both elements are used during the post heating it might be 1 or 2 depending on temp at the IAT. Now each grid heater is 95 AMPs a piece for a total of 190 AMPs total draw so this is why is so critical that your batteries are strong in the winter time!

does this info apply to 24v. i noticed the other day that when cold if i start my truck and let it idle normally, it cycles the grids in 2-5sec intervals(on then off, real quick). but if i hold the pedal for a higher idle the grids stay on for 15-30secs. if i let the rpms fall it goes back to 2-5sec.

I'll double check my books and see if the same rule applies to the 24V... But from a gut feeling I would say Yes!...

The 24v's are the same when it comes to grid heater time.IF anyone installs a Banks Twin Ram intake on their 12v it may take an extra cycle of the grids to get the truck to start as smoothly as it did when they had the factory intake horn on it.In the Twin Ram the grids are split one for each runner and it may mean a little more time to start when its really cold outside.......Andy

You know its cold out when you have had it plugged in all night and the Intake heaters still stay on for 15-30 seconds.

when i start mine (if i don't touch the pedal) i will go on(5sec), off(7sec),(5sec), off(7sec),etc.i judge their operation by the volt meter on the dash, by the sound of the motor and lights going dim.(am i wrong?)but when i hold the rpms at 1k-1200, the heaters are accurate to mopar1973man's list.does this indicate a problem? my batteries are fresh and i don't have any parasitic drains(no aftermarket lights or stereo).

Don't get mixed up... The times shown in the list are BEFORE you start the engine. Then your looking at the post heating cycle which is very random at best...

ahhhh....that makes sense.i think i might do your high idle/3 cylinder idle trick soon. i like the idea of the grids running for longer periods on cold starts...i makes me think it will warm up faster.

Edited December 23, 200915 yr by guesswho512
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