Engine/Transmission (1994 - 1998) Need quick emergency help from a 1997 owner please

[Coalsmoke]

Need quick help from a 1997 owner please

We are hours away from purchasing a used 1997 CTD for my dad with 137,000miles, and we are going to go do the final inspection on it in about 4 hours (it is a bit of a drive away from here). However, it was just noticed that there are a couple of wires under the hood that are disconnected. I think that they are maybe the ground wires or power wires for the grid heater because they are large gauge and are black. They are located on the drivers side of the engine compartment up on the fender. They come out of the wiring harness by the engine (below the fuel pump area) and go into what looks like a relay of some sort (there are two of these black relays, one for each wire). from the relays come these two wires where they are joined together in a connector with an eyelet for mounting it to a battery or a ground source or somewhere, and this is the end that is disconnected. My 95 difffers in design and can't be used to compare, so I am hoping that someone with a 96-97 could please quickly pop their hood and see if they have these wires and where this junction is mounted (battery? grounded to metal?) Any help at all is really appreciated guys, the chilton and hayes manuals for these trucks don't tell me much of anything about these wires. I'm wondering why this would even be disconnected.



Thank you guys for the help, everything else on this truck looks clean, so fingers crossed there will soon be another CTD in the family.

 

[drrhoades]

From memory, cant go and look at my truck right now. They sound like the block heater wires. The two wires are connected with bolts / screws infront of the intake.

 

[Coalsmoke]

The wires are the same gauge as the block heater wires, and the wires are hooked up on the intake side, but it is this other end that I think is taken off. I guess I need to figure a way to get test the grid heater. What about taking off the intake manifold, turning the key, and feeling for heat?

 

[SRadke]

Block heater is on the passenger side, this sounds like grid heater. The grid is powered by black wires, nealy as large as a pencil that connect to the side of the intake just below the horn. Follow those back, they should attach to a pair of relays. Not sure where they're mounted.



-Scott

 

[Coalsmoke]

you're right, I meant to say grid heater, brain fart. I went out and looked at my truck some more and finally found the relays (they hid the relays in a different spot on the 95s) so I am sure that it is the grid heater wires. I tried to follow the wires back on the truck at the dealers lot that we are considering, but, it goes into the wiring harness and gets lost there, and I didn't think he would think too kindly to me cutting the harness open.

 

[SRadke]

If the grids are working the volt meter will be low when you start the truck on a cool day. This would be easy to see. If it's cool and you start the truck the voltage jumps right up to 13 the grids are probably no working. None of that headlight dimming cycling that you usually get.



-Scott

 

[Coalsmoke]

that was my initial thought but it is too warm here now to get them to kick on. about 20 C here right now. Is there a special gasket that could get ruined if I remove the intake manifold to inspect the heaters?

 

[SRadke]

No, there's a gasket in there but I've never ruined one taking it apart. You could always take an ohm meter and check the resistance between the leads that are disconnected. Should be easy to tell if it's a resistance heater.

 

[drrhoades]

Oops I meant grid heater. Sorry

 

[Coalsmoke]

drhoades, seems to be a common slip of the toungue



SRadke, good idea. I'm going to go get some numbers off of mine now, see what the resistance is and then maybe we can figure out whether they are working or not. Think I'll pull my intake off too, and see if it is easy to check that way.



This truck has some grass growing out of it, and the tires are a bit checked and cracked. Needless to say, it is evident that this truck was sitting for a little while. Is it possible that someone dosconnected the heater wires before stroring? Although, they shouldn't go on without the ignition being turned on.

 

[Dave M]

Sorry I'm Late...But Lotsa Pics

I have a 97 and took pic's tonight of the relays your talking about on the drivers side fender below the battery. Sorry but my truck was at home and I took pics right after I got back from work.



One wire (next to the fender side of each relay) from each relay goes to the positive lead of the battery. You can see these two wires connect together into an eyelet and go up to the battery in the pic. The two wires (away from the fender or towards the engine) both go to the wire bundle directly to the right of the relays and end up on the intake going to the grid heaters I assume.



There are eyelets on the each relay end of the wires and the battery end of the two wires are tied together into an eyelet. At the battery they attach together to the positive post on the bolt that goes thru the battery lead and are secured with a nut.

 

[Dave M]

More Pics:

 

[Dave M]

And more pics:



Here yo can follw the wire bundle to the right of the radiator hose. The two wires exit to the right of the radiator hose and terminate next to the air intake horn... it looks like blue dots on top of the wires where they terminate on the grid heaters... go figure.

 

[Coalsmoke]

thank you guys for all the help with these grid heaters. We bought the truck after going through it one last time. Looks like it has generally been taken care of. The conclusion I have ome to is that the heaters are in working condition, but the relays are not working. Maybe one of the relays was stuck closed and the heater wouldn't turn off so the previous owner disconnected them. That's our best guess. Either way, it will probably just mean a ouple new relays and we'll be in business. Thanks again