Hello,

I have an 89 E350 (former U-Haul) van that the blower has quit. Fuses are all good and cold air comes out but "No Blow" on A/c or Heat. Is this the resistor everyone talks about? If so, where is it?

Thanks
David

 

No. If you lose the resistors, the fan runs full speed. There is a relay just in front of the battery on the passenger side that sometimes goes bad. Mine melted the connector. I just had to clean the connections and all was well.

 

This is not correct, if you loose one or more resistors, the fan won't be able to run on one or more of the lower settings.
So, when the fan wil run on the highest one, your resistorblock is probably the problem.
If it doesn't run at all, you've to look for bad wiring, connectors and that kind off things, or the motor of the fan is gone.
You can test the motor by connecting it straight to the battery.

In my '93 this resistorblock is mounted in the fanhousing, in the motorcompartment, a few screws and you can pull it out.
Maybe it is the same with yours

 

Actually I was correct, except I didn't state it quite correctly. And BTW, it's 'lose', not 'loose.'

If you lose the resistors, the fan will only run on full speed when set to high.

And there are 3 resistors so it's unlikely that you have a resistor block problem. It bypasses the resistor block when on High. Unfortunately, the blower motor circuit is screwy. Ford runs the ground side of the blower through the fan speed switch. They run the +12 volt side through the mode switch.

I have a schematic but it's not quite correct, at least for my 89. Someone at Ford threw in a Thunderbird heat/Air controller and just cut the wires and crimped barrel connectors onto the end of the wires. Neither set of wire colors corresponds to my Haynes schematic. I ended up following my wires from the fan to a relay in front of the battery. That relay is not on the schematic that I can see. I'm not even sure what it's there for.

So anyway, first connect the blower directly to +12 volts. It will likely run as they don't go bad too often. If it runs, then you will have to determine whether its missing ground or 12 volts.

That part is difficult to explain. It's best to have someone with electrical knowledge check it out.

Check this too: https://www.ford-trucks.com/forums/a...0motor%20relay

 

Thanks for this small language lesson, i guess you speak and write as good as Dutch, as i do English?

If it's the same as the 93 model, then the 3 resistors are wired serial, in low all the resistors are working, one speed higher there is one resistor bypassed, another step higher there are 2 resistors bypassed, and in high all 3 off them.
So depends on the resistor, but you can lose one or more of the three lower speeds with one broken resistor.

Probably the blower motor relay, it's controlled by the mode switch and swithes the +12 volt of the blower motor.

 

Ik spreek Nederlands slechts goed.

 

Prachtig , maar het maakt niet uit als je het niet zo goed spreekt, het belangrijkste is als je maar begrepen wordt!

 

Ik begrijp wat u beteken (or something like that).

 

in my 87 the relay goofy mentions is for the rear blower. i'd start there if it caused goofys' problem. one wire is a fuse link so check for a melted wire.

the first place my book says to check is ground 203. this is a clip under the dash, left of the steering wheel. there will be 3 wires on it, the black is the ground. it's always a bit loose and can cause all sorts of trouble. if your good with electric troubleshooting, i can give you the step by step continuity check from the book. good luck

 

also, i agree about the resistors but to answer your question they are located on the blower motor assembly above the motor itself. the con has three wires i think. there is also a ground right off the motor, u might want to make sure it is screwed in tight to the firewall.