heater motor not working.

DarkoStoj · Jan 14, 2008

what are the ways I can start troubleshooting how to get my heater motor working again? We bought this 65 mustang and it doesnt have a heater core in and the heater hoses just bypass it, but we want to reinstall it. The motor and box is all there but the heater core isnt. So where do I start checking to see where the problem is?

suki243 · Jan 14, 2008

Does the heater control switch work? its a switch above all the heater control levers, if that doesn't work, replace that, if it works, and there is voltage coming through then the heater motor has to be replaced.

Here is a wiring diagram for you, it has the wires color coded for you

http://midlife66.com/wiring/66acces1.jpg

ForceFed70 · Jan 14, 2008

I'd start by measuring the voltage at the blower motor. No voltage means a wiring or switch failure, +12V indicates a failure of the motor itself.

Tim65GT · Jan 14, 2008

Here is a simplified diagram of the blower circuit.

The motor gets 12v from the fuse box and the switch regulates the ground potential through a resistor assembly.

DarkoStoj · Jan 14, 2008

Tim65GT said:
Here is a simplified diagram of the blower circuit.

The motor gets 12v from the fuse box and the switch regulates the ground potential through a resistor assembly.

NICE! I should be able to figure it out with that.

so there is a fuse that runs to the blower right? I guess that will be the first place i check.

suki243 · Jan 15, 2008

the current from the fuse block runs to the motor. Its the source, its in the engine bay, there are two wires that go to the motor, check the current on the brown one. But when i wired mine, i remember that the wires had become black and hard with dirt and buildup so check both wires i guess.
If no current is being received there, then check the fuse box for a fuse. I'm not sure if the heater has its own fuse, i doubt it, its probably on the accessory fuse
If there is current. then make sure that there is a wire plugged into the heater box prongs, theres a set of three and one below. The one on the bottom is supposed to receive current from the back of the heater motor. So check if the wire is still in tact using an ohm meter.
Im not 100% sure how to test the switch itself.

spirockp · Jan 15, 2008

OK funny I just did this myself. I guess winter is here and we all would like some heat.

Step 1. Hook the 2 wires coming out of the fan and connect them to the battery. Doesn't matter which one goes where, we,re just seeing if it spins.

Step 2. If that works reconnect them. Turn the ignition on. Take the wire, should be yellow, off of the resister on the heater box and ground it. The fan should also spin.

Step 3. If all that worked, unconnect the wires coming from the heater switch and connected to the resister. Take the same yellow wire and connect it to one of the 3 wires coming from the switch. By doing this you are bypassing the resister. Try to turn on the fan by switching to low, medium, or high on the heater switch. One should turn on the fan.

Step 4. If all that worked, replace the resister. That's what I needed to do.

Good Luck.

DarkoStoj · Jan 15, 2008

spirockp said:
OK funny I just did this myself. I guess winter is here and we all would like some heat.

Step 1. Hook the 2 wires coming out of the fan and connect them to the battery. Doesn't matter which one goes where, we,re just seeing if it spins.

Step 2. If that works reconnect them. Turn the ignition on. Take the wire, should be yellow, off of the resister on the heater box and ground it. The fan should also spin.

Step 3. If all that worked, unconnect the wires coming from the heater switch and connected to the resister. Take the same yellow wire and connect it to one of the 3 wires coming from the switch. By doing this you are bypassing the resister. Try to turn on the fan by switching to low, medium, or high on the heater switch. One should turn on the fan.

Step 4. If all that worked, replace the resister. That's what I needed to do.

Good Luck.

PERFECT! this is exactly what i was looking for. Thanks!

spirockp · Jan 18, 2008

DarkoStoj, did you get it resolved?

DarkoStoj · Jan 18, 2008

spirockp said:
DarkoStoj, did you get it resolved?

its been way too bitter cold to even mess with it right now. I'm going to start on it as soon as we get a warmer day here.

heater motor not working.

DarkoStoj

suki243

Member

ForceFed70

That's why they call it "dope"

Tim65GT

Active Member

Attachments

DarkoStoj

Attachments

suki243

Member

spirockp

DarkoStoj

spirockp

DarkoStoj

Similar threads

heater motor not working.

Member

That's why they call it "dope"

Active Member

Attachments

Attachments

Member

Similar threads

Privacy & Transparency

Privacy & Transparency