I bought both the Haynes and Chilton manuals but for some reason they both are missing the wiring diagram for the heat / air conditioning system :-(

Or maybe someone can give me a clue. My heater blower will only work when its on the high setting. I poked around and found a connetor with a melted pin. The connector is attached to the air plenum (my description) on the passenger side of the vehicle. I am guessing that this air plenum is where all the air for the air conditioning system goes through.
Anyway I took this object off the plenum to see what it is and I'm not exactly sure what it does. There are some coils of wire in the device and I believe four wires going to it. When I play with the melted pin I can get the air blower to work on all speeds. But I need to know were these wires go and what is that device so I can find out why the pin melted in the first place. Hence the need for the elusive wiring diagram

1997 Dodge B2500 5.2 liter (318 ci) Full Size Van with air conditioning.


Thank You

 

If you're looking under the hood, passenger side, big black box, about 16 inches straight above the blower motor and looking at a flat 4-wire connector, then you're in the right spot...that's the blower motor resistor that gives you the different speeds. It's about $20 for the part from the dealer (only place to get it).Also, since you have a melted pin,you'll have to get the repair pigtail from the dealer (about $55), part #5019941AA.

 

Well that was fast, Thanks for your help. I suppose I have to start digging around the wire loom looking for a short. Otherwise I'll melt another pin. If thats the resister it must be connected to the speed switch on the dash.

Thanks again.

 

rather than getting the repair pigtail, Id hit a yard for that part, and you can probably get the resistor there for one price. it is possible if the resistor gets plugged up for it to short out. I'd pull it before you decide you have a short, and you can easilly check by disconencting the switch. and testing from there. Also for haynes, the later years only show the changes from a previos year so if you flip back to the 83 set that will at least give you a good idea. of how it is run.

 

Pep-Boys and AutoZone carry the blower motor resistor too. Mine was $12 at AutoZone.

Alloro is correct if you burned the wire harnes and connector going to the blower motor resistor. Order the part from the dealer if it's that bad of shape.

Dodge Caravans too are greatly known for this problem back in the 1990's.

 

I think I found the problem. There was a wire with conductor exposed near the speed switch. I patched it up and tried it out. Works fine now but the pin is in bad shape, but I think I can fix it up.

 

That beat up pin is actually still getting hot, in fact it is getting hotter because it is already burnt up. Scrub both parts with a wire brush until they shine for a good contact. I did this when I got my van and had a noticeable improvement in blower speed and as a side benefit the wire stays cooler too! Less energy is being wasted pushing electrons across a crummy connection which has much in common with a light bulb filament. If you find some wires getting hot with use, try going up a gauge in wire size and it should take care of it.

hot wires == shorter part life.

 

Did anyone find the 1997 dodge b2500 wiring diagram?

The switch on my dash that controls the rear air conditioner is not getting any power. I've traced it to some sort of switch/relay under the hood and wires have been cut but I'm not sure where they originally went.

Does anyone know anything about this?