• Notice for iPhone users: DO NOT use the image size reduction option when uploading photos to the forum. This causes portrait images to post as landscape. We have added a warning to the image insert pop-up as well.

Heater motor wiring

Raven

Raven

Legacy Registered User
City
Glen Rose
State
tx
Can anyone post a picture of the wire that runs to the heater motor? I did the up-grade today, but noticed that my old motor did not have a wire for power.

I looked but failed to find a wire with a connecter for the motor. My guess is that the previous owner just cut the wire off. I also seemed to have misplaced my Chilton’s, so I have no reference.

Thanks
SC
 
It should be hanging out somewhere under your battery tray. Bullet looking connector, IIRC.
 
I did not see anything when I installed the motor. Does the wire you are talking about come out of the firewall by the motor, or does it come off the wiring from the motor?

Having not ever seen this wire I'm not sure where it comes from.

SC
 
Here you go. It's a light brown wire that connects directly to your heater motor thru your firewall. Look under your battery tray, as noted above.
 
The wire is a tan color, and has a 1/4" quick disconnect end on it. About 8" away, there is a rubber bullet connector, the end closer to the fan is the male end. That wire goes thru the loom at the top of the firewall over to the bulkhead connector, then from there to the fan switch.
The fan switch has 12V in, and three other wires that go to the resistor block mounted to the heater box on the passenger side. When you turn the switch to position one, both resistors are connected, 12v goes thru them and sends about 8v out to the fan. In position two, one resistor is taken out of the circuit, sending about 10v to the fan. In position three, both resistors are taken out of the circuit, and a full 12v goes directly to the fan.
 
Thanks for the help guys!

What I am trying to figure out is "That wire goes thru the loom at the top of the firewall over to the bulkhead connector, then from there to the fan switch."

How I can locate this wire, where does it come out of the harness at?

Thanks
SC
 
If you don't readily see it hanging out, maybe it was stuffed back in the loom, open your wire loom and locate the brown single wire with the connector on it, if it's been cut off, put another connector on it, just make sure it will reach the motor. Way to make sure you've got the correct wire it is to have someone switch the motor switch on and off while you put a voltmeter to the wire you're testing...... ground one side and put the other to the wire you think it might be. When the switch is turned on and the VM gives you a reading, that's probably the one. Then run a test lead to the motor from that wire to see if switch works, if it does, you're in business.
....I think!


Raven said:
Thanks for the help guys!

What I am trying to figure out is "That wire goes thru the loom at the top of the firewall over to the bulkhead connector, then from there to the fan switch."

How I can locate this wire, where does it come out of the harness at?

Thanks
SC
Click to expand...
 
Thanks Cabel!

My heater fan had stopped working; not a big deal since I'm in Southern California. But it bugged me. I assumed I would have to change out the blower at some point. After seeing the photo you posted, I checked under the battery tray; sure enough, the tab was there, no wire. I found it loitering by the engine block. It's back in place. Thanks!
 
The fan wire comes out of the loom as it transitions from the firewall to the engine, on the passenger side. Should just be out there by itself, traversing across to the fan. The section between the rubber plug and the fan body has heat resistant jacketing on it, probably for the 304 option in earlier Jeeps, so it didn't get melted on the passenger side exhaust.
 
Update & Block heater

Guys thanks again for the input. The wire was just where you said it would be, the shielding helped in the elimination process.....the idiot who owned her before me had the wire tied directly to the positive terminal on the battery...no wonder it kept blowing the fuses!!

Now that the blower is working fine I'm trying to figure out why the air is only warm. I re-moved what I was told was a "block heater" from the heater lines. I'm going to try re-placing the thermostat next trip. The reason I bring up the block heater is that maybe in by-passing this I am not allowing the correct flow for the heater?? Has anyone ever re-moved one of these block heaters before??

Maybe it is just the thermostat or possibly the lack of one. I did not have time to check it out this trip….horses water trough froze & busted the pipes…..

Thanks
SC
 
You must log in or register to reply here.
Back
Top