2nd Gen Non-Engine/Transmission Heater Grid burned Up?

[Junior]

Hey guys came out to doctors to discover my truck had smoke coming out of the hood. Quickly popped the hood and saw the 2 wires going to the heater grid burning up. The rubber that was on the boots at teh connection was melted right off. So disconnected them rather quickly and soon discoverd after that it stopped smoking. I am assuming my heater grid is bad. Anybody else out there had one go. What is price of new one? Should i be checking for something else wrong?

 

[Joe G.]

The heater grid may or not be bad. But I'll bet the solenoid for the heater is stuck on.

 

[PC12Driver]

I agree. Trace the heater grid wires back and you'll find the relays mounted just below the battery/power distribution block area. With the key off there shouldn't be any juice going to the heater unless a relay stuck.



You're lucky you caught it.

 

[Junior]

Ok i will check but if the solenoid or heater relay is bad what do i do. Change that out, or what? Let me know, not to familiar with this part of the truck yet?





Thanks for the info so far.

 

[PC12Driver]

Yep, just swap out the bad heater grid relay. There are two. Most likely just one is bad. The heater grid has two hot cables (side by side at the grid, on the back side) and one ground (on the front side, that just loops to one of the intake horn bolts). Follow the hot cables away from the grid and you'll find the relays. They should be easy to get to. Then it's just a matter of figuring out which one's bad (melted wire or mulitmeter; the relays are normally open - no continuity) and swapping it out. If the cable going to the grid looks cooked, replace it too.



Also check around the intake horn/grid area for damage (i. e. melted metal, maybe replace the paper gaskets). Some folks have had fires started because the grids stayed on. You're lucky you caught it.



Public service tip: It's always a good idea to check the voltmeter once you're on the road to make sure it's back up to 14v-ish. If it's sagging around 12v or below either you're not charging or the grid is stuck on.

 

[GAmes]

The small hot wires are always hot when the key is on. The ECM or PCM supplies the ground that closes the relays. You can test the relays to see if one or both are closed by checking continuity between the large terminals. If you decide to buy OEM they come as a set. The same thing happened to mine when it was still under warranty. I'll see if I can find the dealers receipt to see what they replaced.



on edit; Not only the relays were replaced, the alternator and both batteries were too.

 

[Junior]

Does anybody have an idea where to find part number for the solenoids.



I will just replace solenoids if not to much $$$. Also, need gaskets for the heater grid because i screwed them up, while trying to cool everything off. I will also get wires since the rubber melted off. It got so hot the intake is discolored brown.



Should i replace the heater grid?



Anything else i should check?



thanks for all the info so far.



Where do i get Optima yellow tops guys?

 

[RBallard]

When it happened to me I just replaced the relays, they come as a pair on a bracket and although I can't recall how much I paid I thought they were was pricey for relays. It might have been $40-$60. I took my air horn off and heaters off just too make sure all was well. The heaters are pretty tough, I highly doubt you need to replace them but if you take them off you will need to replace the gaskets and prepare to do some scraping.

 

[Thomas]

Does anybody have an idea where to find part number for the solenoids...

From the model year 2000 parts catalog: P/N 56026842 RELAY, Electrical Air Intake Heater