I've asked about this like a million times and have never gotten any good help. I had a electrical surge months and months ago, since then my blower motor for my heater hasn't worked, i swapped out a 87 motor, but i seemed dead. just today i bought a brand freaking new heater motor, i hooked it directly up to the battery, and it didn't spin.

Do the motors have a safety feature where you can't do that? i installed the motor in the car, and then directly put power to it, still nothing. Whats wrong?

Its pretty cold still here in wyoming and i haven't had a heater in a long time, i go to school early in the morning and get back from work late at night, i need the heat to defrost and frankly survive. any help would be appreciated.

Is there any in-line fuses that might be blown? wires that might have been damaged? anything, just throw things out there.

The AC was taken all the way off, would that effect it? would vaccum effect it at all?

I will check this in the morning, i hope i have some help.

The car is a 1984 z28, after market 350 if it matters.

the carb has some vaccum plugs in it, would that effect anything?

2 things i don't know alot about, electronics, and vaccum. please help me i really need it.
thanks in advance

 

Since the A/C was removed, no telling what can be your problem. Especially of the heater box on the firewall was removed too.

My first inclination as to your blower motor not working is a faulty blower resistor. The power for the blower runs through the resistor. The resistor is what allows the blower to have different speeds.

The resistor is someplace in the heater box on the firewall.

You hooked up a new motor directly to the battery and the motor didn't run? How did you hook it up?

 

The AC was basically off, we just took off the metal compressor piece (?) and a metal line or two.

Today, unless i get more information, i'm going to trace my power lines straight back from the power and clean stuff up and check things out

I took a 14 gauge wire, connected it to the power tab on the motor, then touched the wire to the battery power terminal. nothing. does it need to be grounded to work?? it seems that out of 3 motors, on being brand new, none of them spun in the least. any ideas? advise? anything people i really need help...

 

This is what i attached the power too.

 

Yes. It needs to be grounded. Take a jumper wire and connect it between the -12V and the blower motor flange.

Connect +12V to the terminal like you did and it should run.

Hang on to the motor when you do this. IIRC, that motor puts out some torque.

 

Okay thanks! thats a relief. I'll try it out, how would i test to see if i have a faulty blower resistor?

 

There's a way to check it, but I can't recall how of the top of my head. I'm pretty sure you can use an ohm meter.

 

could you by any chance post a pic as to where i could find the blower motor resistor? it would help a lot

 

I'm heading home to dig in now, i'll check this again in the morning, or possibly later tonight. I have a list of things i'm going to check and do. thanks for the help paulo. anything more anyone has to say will be appreciated.

Anyone know how to check if the low-high switch is bad?

 

This should be the lower resistor (see the small red arrow).



Or just trace the connector from the blower motor terminal back. It should terminate at the blower resistor.

 

Okay sweet, thanks. So yesterday i took everything apart and did a couple of things. I searched about a million threads and composed a list of things it could be. I found out there are 2 connectors that tend to go bad, and to replace them with some heavy duty terminals, i also checked the relay and the resistor. i did everything, still nothing worked, so in a final act of desperation i connected the ground straight to the batter, fixed almost everything.

I'm not sure if replacing the connectors helped, as well as taking a wire brush to the resistor tabs and the relay tabs, but it doesn't matter, at least i know i wont have to replace the connectors in the future if they weren't bad.

Only problem, is i don't have HIGH speed, i got the lower three, but when i click it to high it all just turns off. suggestions?

 

Yeah, I have that same problem too. My A/C is gone and the heater works fine, but when I turn it to high it's out. I haven't figured it out yet.

 

I'm figuring it has something to do with the relay? I've heard the resistor only controls the bottom 3 speeds, somehow the relay isn't feeding the full 12V to the motor, idk, i'll look around.

Beautiful 'maro by the way