Trying to get at least the blower motor working for a start in my 1987 Dodge D150 318 with AC. It has never worked since I bought the truck.

Does anyone have a good wiring diagram? No power even to the fuse box.

I pulled out the controller and everything looks like it functions. Wiring harnesses are in good shape. Giving everything a general cleaning and inspection while I has the dash ripped up for the interior light fix.

 

if there is no power even at the fuse box with the key in the run position the orange fusible link attached to the pink wire is likely bad. these are under the hood on the drivers side fender.
if you would like to try testing for power at the ignition switch connector you can. it will verify that the fusible link is bad. battery 2 is what you going to test. it should be pink.

 

Awesome I’ll test at the ignition switch. Where do you find these diagrams? Are they in the Chrysler service manual?

What gauge of wire are these links?

 

there are lots of diagrams on the internet. been doing it long enough i have most of the common diagrams needed in 1 folder. some are from service manual or others are from elseware.

i believe it should be 20 gauge fusible link. some people will remove the fusible links and replace it with a fuse panel. they are not quite as good as fusible links but as long as you got spare fuses it should never leave you stranded.

 

Thank you. I have a service manual on the way. I’ll replace the fusible link so I can learn how to do that, maybe put a fuse box in the future!

 

So I scraped away the grime on the wire and it is pink. I’ve looked around at fuse link color-size guides and can’t find pink.

The black “boot” looking thing at the end of the fuse link says 12. I’m guessing that’s the gauge wire it protects, so the fuse link would be 16? Hopefully when my service manual gets here it will list the gauge of that wire.

Alternatively, if I did replace that fuse link with an inline fuse, I wonder what gauge wire I would need and what amperage fuse. I’m not sure what else that fuse link powers because I don’t have my service manual!

 

the orange fusible link should be 20 gauge. the pink wire it attaches to looks to be 12 gauge. that circuit might be ok with a 30 amp fuse but i think if you were replacing the other orange fusible link i think it would need a 40amp fuse because there is much more on that circuit.

 

Thanks, I read your post wrong the first time. Orange fuse link wire is the one to look at replacing, got it!

Would it be a bad idea to probe that fuse link and test it with the multimeter to confirm that’s the issue?

 

you can try probing it but it is somewhat common to see that one fail with age. you could also test for power at the ignition switch connector since that is were the pink wire goes. if you have no power to the pink wire at the ignition switch connector it should be the fusible link. if there is power at the connector then there is likely an issue with the ignition switch.

 

Update: it works!!

I used a penetrating probe and confirmed the pink/black wire off the orange 20g fusible link was not getting any voltage.

Spliced in a new fusible link and managed to get power at least to the fuse box.

Hooked up the proper connector to the new blower motor and connect everything. Blend door wouldn’t move with the cable, so I blasted it with some penetrating oil and operated it by hand behind the glove box to get it going again.

To my amazement everything works like it should! AC, heat, defrost, etc. Thanks for all the help!

PS, anyone know where I can get one of those caps on the end of the temperature selector arm (see photo)? I can’t think of their real name, so Google isn’t helping.