Engine/Transmission (1994 - 1998) Need some help troubleshooting my Grid's.

[Signal73]

Ive been having trouble in the AM starting, so I went out today to see what was up. Temp around 40° today, Get the wait to start light for approx 10 sec. and after that the light goes off and a click is heard in the engine compartment at the same time. I took off the Horn and felt the grids when they were supposed to be warming, they were cold to the touch. Also probed the terminals that hook to the intake for 12V coming in and no power to there. I looked for a fuse for the Grids but couldnt find on in the engine compartment or in the fuse block in the pass comp. Where do I start looking from here. My truck stalls about 3 times and smokes (more then usual :-laf ) on startup.

Thanks, Jim

 

[Joe G.]

Look below the driver's side battery. There are two relays. These relays connect the heater grid to the batteries. If the relays appear to be working check the terminals on the grid for 12 volts. If you have 12 volts at the terminals remove the cables and check with an ohmmeter to see if you have continuity from the terminals to ground.



If your truck is stalling your idle is probably too low. I start mine in 40° weather without messing around waiting for the light to go out. It starts and runs fine. My habit since I live where it does not get cold is to start and go, ignoring the wait to start light. It gets down in the 40s and high 30s a lot in the winter but seldom any colder. I started like that in 18° degree weather in Utah once. It started and banged around for a little, but smoothed right out pretty quickly. No stalling.

 

[Vaughn MacKenzie]

Mine starts nice 'n smooth with temps in upper 20s without the grid heater. I had it unplugged for troubleshooting last winter & forgot to hook it back up

 

[JFaughn]

I think that you have fuseable links at battery for relays.

 

[Signal73]

OK, I have no power to the grid, checking it with a test lite on the 2 terminals. My idle is 750 when the A/C is on according to the tach, but it takes a few seconds to get it up to 750 on the first start. Any other imput would be appreciated. Im gonna go out now with a flashlight and see if I can find the elay and check the fusible links out.

Thanks, Jim

 

[JFaughn]

It helps if you have 2 people 1 to turn key while your under hood , the heater is located under the air tube and above the intake manifold with cables going to it follow the cables back to the relays/solinoids , on mine there are 2 that are on the drivers fender , and there should be cables going from there to batt. the small wires that get there signal from the key sw. so what your looking for is power at all times at the cables coming from the batt. if not then check fuseable links , then with the 2nd person truning key to run posission the small wire and the other cable should now have power until the lite on dash goes out , after truning the key to start posission the relays cycle on and off for a little while to help it run smothly .

 

[Signal73]

It helps if you have 2 people 1 to turn key while your under hood , the heater is located under the air tube and above the intake manifold with cables going to it follow the cables back to the relays/solinoids , on mine there are 2 that are on the drivers fender , and there should be cables going from there to batt. the small wires that get there signal from the key sw. so what your looking for is power at all times at the cables coming from the batt. if not then check fuseable links , then with the 2nd person truning key to run posission the small wire and the other cable should now have power until the lite on dash goes out , after truning the key to start posission the relays cycle on and off for a little while to help it run smothly .

I was doing the timed 10 second olympic sprint from the cab to the eng. compartment before the light went off.

Well what I found was power to the little wires.

power from the batt to the relay. (links good) but no power to the other side of the relay.

1 was clicking after 10 sec. shutting off I guess, other one wasnt. even the one that was clicking didnt have juce to the grid side of the relay so Im assuming new relays are in order.

They are awfully corroded and rusty, I couldnt even break the connections without the whole stud spinning.

 

[Signal73]

Ok found this nice writeup by got smoke here Got some relays on order, Ill let you guys know how I make out Oo.

 

[Signal73]

Update!

Got the grid relays from UPS last night and installed them. We had temps in the high 30's here last night, went out this am and turned the key and waited for the WTS lamp to go out (10 sec) and fired her up and BINGO. much better starting, MUUUUUCH less blue/white smoke And now the volt meter is doing the happy dance so at least now I know they are firing. Thanks guys now Im not smoking out the neighbors

 

[Got Smoke?]

Glad to know I've helped another TDR brethern.

 

[Willys]

Glad to see you've got it working!



Is the rpm coming up to 750 better now? Mine wants to run real slow when I first start it on a cold day, but will run at 750-800 when it warms up.

 

[Jim Fulmer]

Just thought I would piggy back on this thread. If your going down the road at night(you see it better) and the lights are quickly dimming then back to full(like a blink) take the inlet air temp sensor out and clean it off. If it gets dirty it will give a bad signal to the PCM to turn the grids on... ... ... . I usually fight this once a year or so.



My lower compression motor doesn't like a cold start without grids when it's down in the 40's like lately, with grids working it's just fine.



Jim

 

[DieselMinded]

https://www.turbodieselregister.com/forums/showthread.php?t=142915&page=1&pp=15



Just went threw this my self



DM

 

[Signal73]

Got smoke, those relays are monsters compared to the stockers. Hope to get lots of service from them. Willys, I also have the slow to rise idle on cold starts, But I need to make some more observations before I know if it helped it any. The 1 day I started it up when it was cold so far I was running around w/the test light to make sure I was firing and didnt pay much attention to the idle. I didnt have the stalling problem though, so mebbe it helped it some.

 

[Willys]

I checked the voltage on both this morning, mine are working(11-12V IIRC). I still think the timing has slipped a little in mine...

 

[J Shocik]

Just wondering...

Is this a fairly common problem, the relays not working?? I notice when I start my truck lately, my alt. needle doesn't "dance" any more. Looks like I'll be playing with the test light soon.

 

[Signal73]

Its a real simple system. Check the fusible links, and check the relays. I guess the grid itself could go bad too, but the others seem more fragile. PM me if you need any aftermarket part info for relays, etc.

 

[J Shocik]

To let others know, I checked the fuseable links w/a test light & am getting power to the relays. With my son helping, turned ignition on, WTS light on, & tested for power to grids. Power to one side, nothing on the other, so I'll be calling Allied electronics Mon, AM. for new relays.

 

[Got Smoke?]

Mine are still working great and I installed them the end of last year or first of this year! Oo.



Although I did plug my truck up the other night when it got in the 20's I think. :-laf Its nice not to have to wait for heat. Especially when your running late for work! :-laf

 

[J Shocik]

From Got Smoke:

Glad to know I've helped another TDR brethern.

GS, I am following the link in reply #8, which is your repair of this problem. Thought you'd like to know you're helping another member in trouble. John