Where is the best and most reasonable place to buy thos solonoids/relays that are used for you grid heaters? My grid heaters do not work at all, although I dont know where the problem is or why.....I was going to replace the relays(if that is the name of them). I already purchased the replacement wires going both to and from the relays, now I need to find the proper relays.

Also, is there any way to test these to see if they are working? They were corroded and I cleaned them up the best I could, but still nothing working.

Another question, does the ecm control these? Is there anything else to change or check, to get them working? TIA

 

http://dens-site.net/Dodge_CTD/Grid_Heater_Relays/
I cleaned up my grid relays as per Den`s writeup, worked for me, it`s easy to do, just take yer time.

 

Grainger’s or any decent HVAC supplier will have them; it is a White Rodgers part and nothing specific to Cummins.
Jim

 

http://www.mouser.com/search/Product...key802-120-901

Yes, the PCM (or the brain box on non-intercooled trucks) runs the grid heater relays.

 

What is there for a sensor that tells the truck whether or not they come on, or activate? Something has to tell someting else to run the relays, maybe I should start with that?

 

Yes, the air temp sensor on the intake does that. On the non-intercooled trucks, if you unplug the sensor and turn on the key the grids should activate and the WTS light should blink.

The grids shouldn't kick on until the temp gets below 59 degrees. It's not exact, my truck doesn't run the grids until the low 50's.

Early '89's don't run the grids until below 15 degrees.

 

Found the problem. I went to a local parts store and was going to order a new puter for it. They had many different p/n's for it, so I told them I would go home and take it off to verify whatever info was on it.

Removed it only to find out the bolt that holds it in wasnt tight. I removed the connector and the whole inside was very dirty. I cleaned it all up and put it back togther. Upon starting it up this morning, wait to start light worked properly, fired right up and even cycled.

I feel like I just saved 200+ on my car insurance....

Now if I could just get the speedo to work properly and the oil pressure gauge to work right, I'd be in business. Thanks as usual for the help !

 

Well, that was easy!

 

What tool do you use to get the oil pressure unit off with? Socket, wrench?
HAMMER

 

Special socket.

 

on the grid heater topic... The guy before me has a switch hooked up that you push up or down to i guess get the grid heaters warm. The switch is spring loaded and automatically centers in the off position. The wait to start light doesn't work.

So I guess my questions are How long do I need to hold that switch up before I start the truck? and Is this going to cause an issue during the winter as this is the first winter for me and the truck?

It did its winters in Arizona before I bought it.

 

Until the temps get below 20 degrees there's no need to touch the switch. Below that give it 30 seconds.

The grids are there more for emissions purposes than as a starting aid.

 

Were the grid are wires you bought specific wires or did you just buy the right gauge. I apparently hooked my grid air up wrong and burnt the wires, need to get some new ones.

 

Hi, I have a 92 Intercooled. How do you test the Intake Temp Sensor?

(the wait to start blinks like crazy , or sometimes it won't blink until the engine is warmed up. Once it's warmed up, it it's ok, or perhaps the PCM is just ignoring it?)

Thanks!
Ford

 

First make sure the connector to the sensor is tight. After many years the springiness of the contacts in the plug weaken. You can sometimes use a pick or a jewelers screwdriver to pry the pins a bit tighter by sticking it in between the ring of the pin and the housing. You might be able to disassemble the plug itself to gently squeeze the contacts.

Mine did the same thing but I fixed it by unplugging and replugging the connector.

Edwin