1983 Datsun/Nissan 720 Blower motor issues.

[Bigorange1962]

Hi all, I'm new here and looking for some help.. I have a 1983 Nissan 720 pickup and the blower motor doesn't work when it's below freezing, after the temperature rises above freezing the blower works fine. I've replaced the blower motor with a new one and it still does the same thing. Driving to work bundled up is getting old. Help

[Rev_D21]

Is the motor trying to turn or is something blocking it when it freezes? Also have you unplugged it and checked for power at the connector when it's freezing out?

[Bigorange1962]

I have reached behind the cover and turned the fan with
With my fingers,so the fan will turn. There is power at the connector as well. I have notice when I turn the fan on, sometimes I get a buzz sound ( for a brief second) coming from under the dash on the passenger side.. I looked today and there is a small box mounted to the side panel, just below the dash.It's about 1 inch wide and about 3 inches long.Not sure what it's for. Looking in my Haynes book now. It doesn't make the sound every time.

[flinterman2000]

How much electrical experience do you have? Do you have some time to spare? Yes to any or both, try running a direct to the blower when its freezing. If it runs then the relay is the problem. Make sure the ground os good before you do anything.

[Bigorange1962]

Some to both. I've bypassed the relay and the blower works fine and I've replaced the relays twice. This is the second new new blower as well.Straight wired the blower and it works fine.....when it's put together it still does the same, doesn't work with low temps outside. I'm going to replace the resister, it's the only thing I have left besides the ignition switch. I will be checking the outside air flap to make sure it's shut tight, just to make sure there's not any moisture get in and freezing up the motor. Even tho I haven't seen any when I replaced the blower.

[flinterman2000]

I would by-pass the relay and wire in a new relay completely separate to the original. I installed a universal blower for the AC complete with on/off switch and rotary temp control.

http://s658.photobucket.com/user/flinte ... sort=3&o=0