Cannot Get Blower Motor To Run-TW25

[FOMOCO Farmer]

Posted a while back about burning up blower motors on this TW25. As it turns out the motors were not bad. I hooked them up to a battery and they work. Someone said it might be the cab relay. I changed that and also the fan switch. Still no blower. Fuse is good, 12v to relay but no voltage to switch. What else could it be? Thanks!!
 

[sotxbill]

[FOMOCO Farmer]

Yes fuse checked. I have 12 volt to all 3 terminals of the cab relay.
 

[RodinNS]

The main bulkhead multi-connector under the cab... This is the one with the 3 10ga wires. Probably got the green disease if it's not just burnt up.
Wire around it with blade connectors and seal it all with bead sealer or brush on tape.

Rod
 

[Hobo,NC]

[RodinNS]

'Q' and 'Super Q' cabs have a power distribution or ignition load relay buried under the dash. It takes all of the heavy cab electrical loads. So... it can be bad. The bulkhead connectors that feed it can be bad. It will for all the world present itself as a bad ground when there's a problem in that circuit. The more loads you turn on, the weirder things get. Gauges act up, lights dim, etc. It's generally alack of ability to conduct current in that circuit.

Rod
 

[sotxbill]

That fan motor has multiple leads coming out of it for speeds IIRC. but no voltage at switch and voltage at relay means wire or bulkhead connector.

I pull wires out of bulkhead plastic and put a piece of heat shrink on them over the existing connectors. I usually pull all of them out as the bulkhead is crumbling anyway and cant be reused.. pull em out one by one on each side, remate them and shrink them as the connectors are still good. then silicon up the hole in the cab with the connectors pulled just inside..

otherwise cable is damaged going up to roof.