Help? Grid heater problem

[DEdds]

Hey guys I need some help. My grid heater will cycle on the key but it will not auto cycle like normal, instead my brake box will cycle. Yes my brake box cycles. I looked for crossed wires but cannot find any. Anyone out there experienced this?

 

[JGrefenstette]

are any unusualy dash lights illuminating as it cycles?? i. e. - wait to start, water in fuel, abs, low fuel, check engine, etc??



what kinda temps is it out side? much below 50degrees?

 

[CGauthier]

Hey Jimmy,

What you gettin at with the cold temps? If you're getting at what I think you're getting at, and that's the pcm acts up in cold weather then that blows my mind because i thought it was just me... my wait 2 start light only works when it's fairly warm outside, and lately in the EXTREME low temps we've been having, I've noticed that my battery voltage guage has been becoming a bit irratic on the really cold days, even with the engine hot. The guage would dip (ALOT lower and more irratic than usual... ) and the lights would dim and all that, so the alternator would obviously stop charging for whatever reason. Damn computers.

Carl

 

[Tippin Spotted Cow]

If your voltmeter dips down and hops back up on and off for the first 5 minutes on the road in extreme cold temps, thats your grid heater working. It's supposed to do that. Yes, your headlights will dim also. Thats how much juice that thing takes. The voltmeter will dip down to around 8 volts or so when the grid heater fires up, then itll turn off and the volts will go back up to around 13. If it ever didn't do that, that means your grid heater wasnt working. It will do that if you haven't run your engine in more than about 5 hours and its below 20. Its been negative 5 around here the past few days with wind chill down to 25-30 below zero, and my grid heater will keep cycling even if I leave the truck idle for 10 minutes. Then once I start driving and give it a little load to warm up the motor itll stop cycling after about 5 minutes.

 

[PToombs]

Check for bad grounds. Clean every one you can find, battery terminals, negative post to core support, post to engine block. Engine to cab. Up under dash are a few also. Sounds like the heaters are grounding thru other stuff. Real easy to burn up other things this way.



Carl, yours sounds like the PCM. Daledozer had the same problems with his. He put it in the house overnite, did a quickie install in the morning, and everything worked normal.

 

[JGrefenstette]

Carl,



thats exacly what im getting at. Ive been through thats same mess before. the charging system goes haywire, the warning/dash lights think its christmas time. the pcm is very easy to install and you can find them for rather cheap. let me know if you find that youll be needing a new unit, ill get out my recipt and give you the price along with the website address.

 

[DEdds]

The lights on the dash are fine. It just seems to be my brake box. I guess my brake box gets cold to. Just kidding. My volt meter isn't fluctuating. Therefore i'd say it isn't cycling. Temps have been below 40 degrees for a while. I'd say the pcm is getting ready to lay down. I have cleaned the grounds and no change.

 

[CGauthier]

Wow I never thought a piece of electronic gadgetry like that would feel the cold. That's the first i've heard of something like that.



Thanks Jimmy that's great I'll keep that in mind for sure.



Carl

 

[DEdds]

Yep Probably gonna need a PCM. Anybody got a good source they can recommend.

 

[JGrefenstette]

sure do DEdds. Wholesalemopar - Genuine OEM Parts for Dodge, Chrysler, Jeep & Plymouth.



heres the breakdown of the cost: $24. 30 for shipping... absurd?? Yes, but its worth it due to the good deal. $227. 50 before the core. Comes down to a total of $251. 80. when you send in your old PCM theyll refund you account $125. So after its all said and done, youre only spending $126. 80. not a bad deal i my opinion. ive had mine in for almost a year and who knows how many miles. no issues. hope this helps.

 

[JGrefenstette]

oh and i almost forgot, soak the mounting bolts with PBblaster or somthing of equal strength. i broke a few of them. their terribly rusted and a pain! youll be lucky to get them all out without problems, but count on replacing all of them. their small and cheap, just long a skinny. Good Luck!!

 

[DEdds]

Thank you very much

 

[JGrefenstette]

your welcome, let us know how it turns out and if its fully solves you problems. i cant emagine why it wouldnt, but then again it is a dodge. :-laf