View unanswered posts | View active topics It is currently Mon Mar 19, 2018 8:39 pm

Reply to topic  [ 2 posts ] 
 heater motor is not working 
Author Message

Joined: Sun Jul 28, 2013 4:08 am
Posts: 1
just picked up a 1990 e250 extended van. the heater motor does not work. there is no voltage at the fan speed switch. all fuses that I can find are good. purchased a chiltons manual for wiring diagrams. It seems to have everything except whats in the dash. What a waste of my money. I'm pretty good at following diagrams and troubleshooting but don't know where to start.Is the fan switch supplying grounds instead of voltage or is the problem before the switch? If someone could post a diagram or just walk me thru the circuit I would greatly appreciate it. I could just install a toggle switch and home made harness but would rather fix it correctly. Thanks.

Sun Jul 28, 2013 9:50 am
Lead Flunky

Joined: Mon Jan 23, 2006 7:52 pm
Posts: 108
When you set the ac/heater selector to a position other than off it triggers the blower motor relay, from the relay a orange/red wire supplies 12volts to the blower motor, from the motor a orange/black wire carries the voltage to the fan switch, a heater resistor supplies varying levels of ground to get different speeds.

If the heater fan works on high and no other speeds it is a bad resistor, if it doesn't work at all it could be any of the 3 parts failed.
If you are not getting any voltage on the orange/black wire with the selector switch set to an on position and key on you may have a bad motor.

Sun Jul 28, 2013 6:27 pm
Profile WWW
Display posts from previous:  Sort by  
Reply to topic   [ 2 posts ] 

Who is online

Users browsing this forum: No registered users and 1 guest

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group
Designed by ST Software.