how to disable my gridheaters/convert to manual

[tobaccogrower]

last winter my grid heaters went of the fritz. below 40* there was a buzzing under the hood and took a few seconds till buzzing stopped and hear the relay click and come on. i couldnt solve the issue(followed everyones advice)so just cranked it over soon as i got in.



this year is a diffrent problem. the grids wont come on untill after i start the truck, and they stay on a looong time! i was late a few days ago and they stayed on for at least 10 minutes of driving. my voltage was so low truck wouldnt shift into overdrive.



so, how can i either switch over to a push-on manual switch so i can control when they come on or totally disable them all together. thanks guys!

 

[goodguys75]

I would think that in a cold situation, it would not be wise to disable the grid heater... . I would say it would be hard on the motor... . or maybe not.....

 

[bighammer]

Should be pretty easily done:

Put a switch on the dash and wire it to a heavy duty relay. Run the battery power thru the relay to the heater grid. (might want to have a lighted switch, or a bright indicator light so you don't forget they're on)

 

[HHhuntitall]

Sounds like the factory relays are good..... Just put a push button or momentary toggle on the dash, wired to the input poles already on the solenoids/relays on the fenders. I believe it's a 14guage yellow and orange wire? Can't remember for certain... ..... That would do the same signal input from the manual switch the Air temp sensor does to the relays..... There are two poles on the sides of each of the solenoids, one's a positive feed from the Air temp sensor, the other is a ground. They should have a round, 90* connector on top. Unplugging them will also prevent the Air temp sensor from activating them until you have time to wire in a switch.....

 

[DVolk]

Use a ford style starter relay then 10 guage wire to engergise it with a heavy duty starter button and your good to go

 

[tobaccogrower]

thanks for the quick input guys! if i unplugged them from the air temp sensor would the light on the dash still come on? while the grid heaters are running the light flickers and somtimes it is off. only way i know the heaters are on is the amp guage and the few other things affected by low voltage. they came on in 60* yesterday. does the computer have any control on the grid function?

 

[cerberusiam]

The computer is the only control for the grid function. Sounds like you have some bad connections somewhere or the SBEC is toast.

 

[tobaccogrower]

ok, i disabled the grid relays on the fender. no power to grids but i have current draw. does the computer communicate with the alternator? i didnt have time to check if it was putting out 14v when running this morning but i suspect it may be the problem. same symptoms as before. let the truck idle for 15 minutes this morning and still didnt have 14v on the guage.

 

[cerberusiam]

Well, the computer turns the alternator on to charge if thats what you mean. Charging susyem is managed by the SBEC. Usually when you start seeing multiple problems from the computer controlled items its a computer problem. You have to check all the grounds and battery connection, cables, etc, too make sure there good though. A bad cable will cause many of thes issues.

 

[tobaccogrower]

ill check all the grounds again. where is the sbec in the truck. i unplugged the anti-lock box behind the glove box when i disabled the anti-lock. could this be causing a problem?

also, where does one buy a new sbec if needed? thanks for all the great advise. going to put grids on a push starter button today.

also forgot. ac was intermitant this summer. worked one day then nothing the next. starting to sound like a sbec problem?

 

[Paychk]

The computer is behind the battery, the anti-lock controller is independent to the SBEC. New SBEC, good luck, they can be reman'ed check with napa or the large parts store chains.

 

[cerberusiam]

Yep, sounds like an SBEC problem. Hard to tell for sure bit it does sound like its the issue. A lot of places can get the remanned units. For the most part have had good luck with them but it can be a crap shoot.

 

[DVolk]

Other than possibly the grid heater operation although id bet money on it that it work as well id try plugging
a mini van computer in as they look identical as is the plug in for it

 

[tobaccogrower]

what kind of minivan? i pulled the computer out and cleaned up the connections. still nothing. at least i got the numbers off it. napa said around $200 and it would take a few days. im willing to try the minivan one and put the grids on a button.

 

[DVolk]

That i know of 88 on up to id say 94 or so i plugged a 94 cummins harness into a mini van pc , it wasnt running but the years of mini vans we had and junked here have been from 88 to about 92

 

[DVolk]

I have also heard that there is alternator shops can make the alternators self regulated as well , i also do know that minivan alternators fit are trucks , just swap the pully

 

[tobaccogrower]

my speedo is on the fritz now. workes for one ride the dead the next. is this an associated problem?

napa said they can get the computer but its R&R. they take mine, send it out, repair it and send it back. turn around 10 days. any better alternatives?

 

[DVolk]

id say the speedo is something else as i never seen a electric one on the early mini vans my guess its a connection issue or a striped out componet , mine the odmeter quit for awhile then started again

 

[tobaccogrower]

anyone have any better solutions then being without being without a truck for 10 days using napa? this is my work truck and i depend on it.

 

[cerberusiam]

Try Shucks or one of the other parts houses. They used to able to get them and you just swapped on the spot.

Contacting a ECU rebuilder might work also to limit down time. You pay a core charge but get it back when you turn the old one in. This is assuming they have some in stock ready to go. The availability to demand may be the issue.