grid heaters do not work automaticly so i want jump them with a toggle swich and need to know the leangth of time they stay on when engine is cold.1999 24v

 

Depends where you live....and how cold it is..... and if you plug in or not?

Rule of thumb - 0* to 20* OAT and a cold engine..... 15 sec. Little longer for colder.
Longest I've ever seen is maybe 25 sec.

RJ

 

Why not properly diagnose and repair them???

 

its -25 here and properly fixing the problem will have to wait for nicer weather

 

-25 I would run them for 30 seconds or so. That cold I usually switch them on twice, so a little longer might not hurt.

 

So since we have this thread going.
What if the heater cycles when it is -18C or warmer and then never cycles when it is any colder which it always is here.
Mine has been doing this without fail and as a result, i have to take a cab or use a tiger torch for 40 mins to get the truck started. My block heater, magnetic pan heater and a battery warmer isn't enough to start it when it is -25C or colder.
Is there a temp sensor that is malfunctioning.
Am i on the right track ?
Thanks Gents

 

There is a sensor in the head for the temps. I think it is the rear sensor in a 24v (other one is a MAP sensor), 12v will only have one sensor in the head on the intake side, thats the IAT sensor.

 

I cut this from a post I wrote over on DTR

Well it had to happen... last night on the way home the check gauges lite came on. the Volt gauge was reading very low, so I switched the Juice to read Volts and sure enough I was down to 10.8 to 11.2, I only had a few miles to go, so home I went, parked the truck, fiqured I'd look at it in the morning. The next morning I went to do a couple of quick checks. went to check for power at the field and surprise surprise I had none, actually I had NO voltage anywhere the batteries were stone dead!! when I shut the truck off last night the batteries were low but not dead. they were so bad my battery charger kept popping off when I tried to charge them in the morning. so off to costco for 2 new batteries. on a whim I tested for continuity across the Grid relays and with no batteries in the truck I had continuity....the relay(s) were stuck on!! After installing new batteries and leaving the grid leads off at the battery my truck is charging fine and I have no issues with it. Just to confirm my relays were stuck/fused closed I touched the leads back on the battery and get a arc, so I guess I'll be wiring in a set of Frd starter relays and I will include a way of turning them off unless they are needed for a cold start. as I stated above I thought it was too much unnecessary electrical load when the engine is at 90F and on EVERY hot restart it would cycle the glows. For a normal daily driver maybe there would not be much of an issue but my truck sees more run time and on-off starts in one day than a normal DD would see in 1 week, heck maybe even in two weeks. I have also come to the conclusion that the ECM does NOT take the ALT off-line during glow loads, unless its looking for a load prior to turning the grids on. I say this because when the leads are off (grids dissabled) there is no voltage drop measured at the batteries.
My grids were stuck on all night and of course the truck never burned down but it still hurt to toss another 240$ in batteries that could have been saved

Full thread can be found here:
http://dieseltowingresource.com/showthread.php?t=5428

 

LeaperV12.
I am just curious. Just where do you apply the tiger torch for 45 mins without damaging seals, gaskets etc?

 

olddodgetrucks, from your post, I assume you have already tested the operation of your solenoids by grounding the PCM side?

If so, you really cannot hurt anything by running them too much, except your batteries.

I would push it for 15 seconds, start the thing, then after 30 seconds of run time, hit them again for 10 seconds, repeat about twice, and you should be close enough for government work.

LeaperV12, man I can't believe you have that much of an issue, are you running synthetic oils? My VE pumped 4BT will start at -20F without even being plugged in, much less grid heater, etc.
But yea, I would bet on a temp sensor, why not do a manual pushbutton for the Grids?

 

Yeah, i was too when i was told this method
i keep the flame low and put it under the block, so the flame doesn't touch anything, since there is space between the road and the pan.
As i said, i don't like this either because i have to watch it continuously and after all it is an open flame

 

I checked and there are 2 plugs, maybe both of em are some kind of sensors
which one is my IAT sensor

 

The only reason i bought a Ram was because of the legendary Cummins. I cant believe it myself either. i also have a booster pack so my battery doesn't quit, it still wont start and i want to stay away from ether etc
No i am not running Synthetic, I believe its 10W40 what the previous owner put in. Next oil change and I am in for 0W40

Manual Push button is the best way, just trying to figure out where to hook up a switch to. Ill call Cummins tomorrow anyways to check if they have a sensor available.
I don't mind mechanicals but i try and stay away from electrical stuff
No one even has any manuals available currently not Dodge, not Haynes and not even Cummins

Thanks a full TON Guys

 

Leaper, super simple, you can even leave the automatic functions hooked up.

The Dodge pulls the GH solenoids to ground to activate, so all you are doing is the same thing with a switch, so grab pretty much any pushbutton switch ( actually 2 if you want to remain both automatic and manual, because tied together the grids could not operate independently ) One side of the switch(s) will just go to a good chassis ground, and the other side will go to one of the small terminals on the solenoids. You can find which one, you will have 12V continuous to one of the small leads, and the other will not have any voltage, this is the one you will hook to the other side of the switch.

I personally also added LEDs from Radio Shack to indicate when my grid heaters were physically on. I know, I know, the lights dim, etc, but all that tells you is something is dragging your system down, with the LEDs I can tell if one or both are actually firing.

3 bucks at RS was a good investment.....

 

Are the 12V different than the 24V?, I say this because on my truck the Grids are activated with 12volts from the ECM, not a ground signal ,(asper wiring diagram) I just replaced mine (see sob story above) and used 2 Ford starter solenoids from a ford tempo, when the 2 starter solenoids are bolted to the orginal bracket you must ground the bracket or they will not work I did not even hook up the black/tan wires which are the ground signal, just hooked up the other two wires,(cant remember what colors they were, but they are the "hot" side) One to each solenoid and it works fine, actually I'll try to post a pic of the disassembled orginal grid relay, the internal contacts are pretty small, to be handling 100amps, its no wonder they are known to stick on