blower motor problems!!!!!

[bradley7576]

i can't figure out why my blower motor isn't working. ive got a new blower motor new inside and outside wiring harness' and a new resistor. cant figure it out? any help yall?

[prostreetC-10]

Ah man........I was excited to take a peek. I thought you meant BLOWER MOTOR!!!!!!

[Longhorn Man]

is the ground strap hooked to the blower motor?

[bradley7576]

yes the ground is hooked up and i wish my truck had that engine........ill trade my blower motor for yours! What do you say?

[prostreetC-10]

I'm just trying to figure out why this guy's PS pump is red. Kinda kills the looks of an other wise B_T_T_B motor.

[Longhorn Man]

it's time to start troubleshooting. All it takes is a couple hrs and a test light, real easy to follow the wires and find where the power stops.
Just becouse the part is new doesn't mean it's good, and that's true now more than ever with the overseas parts we are getting.

[bradley7576]

didn't notice the pump till now but i agree

[prostreetC-10]

Are you trying to bench test it or test it in the truck? Maybe get it working on the bench first. If you bought it at a local NAPA or something, don't spend too much time. Just take it back. They are too simple to mess with.

[VetteVet]

You have a pretty simple circuit for the heater so it should be easy to figure out why the blower doesn't work. On the fuse panel there is a fuse marked heat, which is a 3 amp fuse for the heater. It is fed from the ignition key circuit that feeds the fuse panel.

From the fuse panel a brown wire runs to the heater switch and powers it. Then there are 3 wires from there to the resistor, blue, yellow, and orange for the three speeds to the fan. The orange wire comes off the resistor and goes to the fan, and it actually bypasses the resistor as well as provides a path for the other two wires to run through the resistor and to the fan.

Check for 12 volts at the brown wire on the fan switch and then check for 12 volts on each of the switch speeds as you select low, med, and high. If you don't get any voltage anywhere then you'll have to trace the brown wire back to the fuse panel and check the fuse. 3 amps seems small for the fan fuse but that's what it says on the panel.

If you want to check the fan then just run a wire from the battery + post to the fan where the orange wire connects and the fan should run on high speed. Make sure the fan motor is grounded even if you have to run another wire from the negative post to the fan body.

[fixit-p]

The labeled fuse block here >>> http://67-72chevytrucks.com/vboard/s...d.php?t=121515 is incorrect. The 3 amp fuse is for the radio and the fuse below it is 10 amps for heat only and 25 amps for AC. Another quick test you can do is if you find 12 volts on the orange wire at the motor is to check the motor housing itself, if you have 12 volts there as well (your ground is bad) if no voltage is present the the motor has an open circuit.

[VetteVet]

I looked at that picture and when I saw the 3 amp fuse I looked at this one below and it is the same only the block is turned around. The factory must have labeled them wrong. I couldn't believe a 3 amp was enough but I also thought it was for the radio.Ok now I get it, the heat and AC fuse is the same one and if the truck doesn't have AC then use a 10 amp and if the truck has AC it needs a 25 amp fuse. VV

[hugger6933]

I just ran into this on mine last week. I first ran a jumper to the fan, it ran. I next ckecked for fire at the switch, brown was hot. I then jumped from the brown to the others and found my different fan speeds. The fan speed switch is bad. Go to the store no one has one don't want to wait for one to be shipped so I take the switch apart [real easy to do] with the little tabs on back. I then cleaned out the gunk and shined up the contacts with some 1000 grit put it back together and it is perfect. Jim

[bradley7576]

i tested the fan before i put it in and it was fine my prolem seams to be that the plug for the switch has no brown wire coming out of it and i can find only one brown wire thats loose and it has a connector on it that looks like it plugs into another wire......so i took that wire removed the connector and plugged it into the empty spot on the plug to the switch and still nothing just wondering where the brown wire is at on the fuse panel
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[bradley7576]

is there supposed to be a loose brown wire from my fuse box to the switch?

[bradley7576]

Originally Posted by hugger6933

I just ran into this on mine last week. I first ran a jumper to the fan, it ran. I next ckecked for fire at the switch, brown was hot. I then jumped from the brown to the others and found my different fan speeds. The fan speed switch is bad. Go to the store no one has one don't want to wait for one to be shipped so I take the switch apart [real easy to do] with the little tabs on back. I then cleaned out the gunk and shined up the contacts with some 1000 grit put it back together and it is perfect. Jim

can you send me a pic of the plug on your switch? does it have a brown wire coming out of it? if so where does it trace back too?

[fixit-p]

The brown wire goes back to the fuse block, did you check the fuse in the picture Vettevet posted it is the fuse at the upper right labeled Heat.

[oldgold70c10]

Originally Posted by hugger6933

I just ran into this on mine last week. I first ran a jumper to the fan, it ran. I next ckecked for fire at the switch, brown was hot. I then jumped from the brown to the others and found my different fan speeds. The fan speed switch is bad. Go to the store no one has one don't want to wait for one to be shipped so I take the switch apart [real easy to do] with the little tabs on back. I then cleaned out the gunk and shined up the contacts with some 1000 grit put it back together and it is perfect. Jim

That's exactly what I did on mine. Couldn't do that with a newer switch!

To the original poster, I would check the wire running from the switch to the fuse box. Does the loose brown wire you talk of have a connector on the end? Is it bare brass, or is there plastic? I ask because it is easy for the metal terminals to sometimes pull out of the plastic plugs, since they are held in with little spring metal fingers that can break or bend.

[VetteVet]

Well it should go to the back of this. The large brown wire in the center is the acc from the key switch and I think the other brown wire is under the purple wire in the bottom of the pic.



This fuse panel has seen better days.

[bradley7576]

the brown wire had a plastic connector on it but i took it off to place it in the switch plug to plug it in

[Classic Heartbeat]

Are you sure you got the right wire? The brown wire shouldn't have had a plastic connector. It terminal shoves into the plastic connector that plugs into the heater switch. How is your heater switch? Do you feel it click as you slide the lever over? If not that is probably your problem. It also is an easy thing to do to check the brown wire to see if there is power there. WES