Engine/Transmission (1998.5 - 2002) Grid Heater Cycling

[Jetpilot]

Can any one here tell me where its written that our grid heaters shut off once we are up to 22-25 (?) mph. Mine are cycling pretty much all the time until the truck is COMPLETELY warmed up regardless of vehicle speed. I took it to the dealer but so far they have been unable to correct the problem + they couldn't find anywhere that described vehicle speed in relationship to the grid heaters... ...



Doug

 

[Paulsdodge]

My owners manual states this in the starting durg cold weather conditions. 2001

 

[Jetpilot]

Thanks.....



I couldn't find it in my service manual and the dealer had that look of so this will help. Anybody have any ideas to pass along as to why they won't stop cylcing?

 

[DEZLPWR]

Originally posted by Jetpilot

Thanks.....



I couldn't find it in my service manual and the dealer had that look of so this will help. Anybody have any ideas to pass along as to why they won't stop cylcing?

Don't really have an answer to your question, but if you get the Intake Heater System Saver from Practical Solutions, your grid heaters will NEVER cycle when the engine reaches 140* I believe.....

 

[yogibear]

PS makes a 24V Heater Saver that will not let your grid heaters cycle after they reach 125*. I had one on my 00, and it worked great. Chack them out at, www.psdieselproducts.com



Larry

 

[TxDieselKid]

There was a post by Texas Diesel(now Tejas Diesel), about this. It was thought up by the sly fox called WerCummin(same guy with the VGT40). I'll do a search for it when I get some more time.



He told me how to do the fix diferently for the autos when we were in San Antiono, told me he'd e-mail it to me, but never did. That's Dean for ya.



Andrew

 

[Rob Thomas]

Doug,



Page 121 of the owners manual (glove box) not the service manual, top right of page, it states..... " If the vehicle speed exceeds 18 mph, the manifold heaters will shut off".



Later, Rob

 

[WAYNE]

You took your truck to the dealer did they want to test drive it

 

[Rob Thomas]

Originally posted by WAYNE

You took your truck to the dealer did they want to test drive it

LMAO, I can hear the dealer guys now ... " Hey, thats the truck that was in the Mopar magizine, WooooooHooooo" ... ... ..... "Excuse me sir, but we're gonna havta take this truck for a rip, er, I mean, a TEST drive"



Later, Rob

 

[Steve St.Laurent]

Just a guess Doug but do you still have that wire clipped for the speed limiter? Maybe that same wire is used to sense road speed for the grid heaters?

 

[WeirCummin]

Doug,

I did come up with a simple fix for the GH It will only let them cycle when the engine is not running=no oil pressure.



Andrew

He told me how to do the fix diferently for the autos when we were in San Antiono, told me he'd e-mail it to me, but never did. That's Dean for ya.

I thought that as much as your on the forums that you'd have read the fix I'd come up with, but I guess not



Here is what I did to stop the cycling of the GH.



Get yourself a Borg Warner S320 oil pressure switch, it is N. C. (normally closed, open on rise) or equivalent. There is a port on the oil cooler/filter assy, 1/8" NPT. Put the switch there ( for the auto's you will need a 90* elbow due to the extra coolant line for the transmission's liquid to liquid fluid cooler.



For the wiring, it is only the control ground circuit that you are breaking so 16 to 20 gauge wire will work. From the switch you'll want to run a wire to both of the ground terminals on the GH solenoid coils. They are the two that are towards the firewall on each solenoid. The wire can be run in series since the factory wiring is done the same way.



Dean

 

[truckstom]

I've done this fix that Weircummin described. . WORKS GREAT!!

 

[Texas Diesel]

I have nothing but to say about Deans mod, been working just peachy for me.



Good to see you back online Dean, I was worried that you UPS'd yourself somewhere.

 

[Texas Diesel]

I have nothing but to say about Deans mod, been working just peachy for me.



Good to see you back online Dean, I was worried that you UPS'd yourself somewhere.

 

[Jetpilot]

OK found the problem..... It was the disconnected speed limiter wire! I hooked it back up and the grid heaters started working properly. Thanks guys!



Doug

 

[MCummings]

Time for a switch instead of a "hard" disconnect.



I added about 6 feet of wire to the "Speed Limiter" wire that goes to the PCM,, didn't seem to affect it,, but as I found out, '98. 5's don't do the "speed limiter" trick.

 

[barbwire]

hey fellows, I guess I never thought that the grid heater cycling until warm up would harm anything. Can anyone let me know what harm it does? Mine cycles until fairly warm also.

 

[roadranger]

Originally posted by WeirCummin For the wiring, it is only the control ground circuit that you are breaking so 16 to 20 gauge wire will work. From the switch you'll want to run a wire to both of the ground terminals on the GH solenoid coils. They are the two that are towards the firewall on each solenoid. The wire can be run in series since the factory wiring is done the same way. Dean

OK, here's a dumb question, guys...



Where are those GH solenoid coils located on an '01?

 

[truckstom]

on the drivers side under the hood. . stand next to your tire facing the engine, look down. . almost hidden, but they're there... .

 

[bigbrassmonkey]

Hey doug



just hit the nitrous button when the grid is cycling, that'll solve the problem