Blower Motor not working

[Mike Sos]

As a man it takes a lot to ask for help but my wife is staring at me with a disgusted look. My blower motor quit at all speeds. Here is what I have checked and or replaced. I have 12 v at the fuse block, I have continuity at the fuse. I have continuity thru the relay. I replaced the resistor, I pulled the fan hooked to 12v it works, I have a continuity at the ground on the blower plug. I replaced the fan speed control, I have continuity at the fan speed female plug. I saw on another post that the door blend accuator controls the relay and sends 12 v to the blower plug when not in the off position. I have no voltage at the fan plug but do have continuity I have to assume I should change the door blend accuator or could it be the selector switch on the dash itself.

 

[RonD]

Welcome to TRS

The blower motor itself gets 12v from the blower fuse and then thru the blower relay in engine bay fuse box
The blower relay is activated by climate control switch in cab, it uses 12v from fuse 27 in cab fuse box to activate this relay
Blower relay should be activated in ALL settings except OFF

The Blend door also uses the same fuse 27 12v but that is the only connection between the blower motor and blend door, they share a fuse
If both were not working then fuse 27(10amp) would be the issue most likely

Like most, if not all, Ford blower motors the Speed of the blower is control by the blower motors GROUND
For High the speed switch on dash sends a DIRECT Ground to blower motor
For lower speeds the Resistor block is used
This is why you can have HIGH but no lower speeds, a resistor block failure

With key on/engine off
Climate control on any setting except OFF
And fan speed set at HIGH
Check blower motors 2 wires for 12v to battery ground, and Ground to battery positive
One will be missing if blower is not working, assuming blower motor is not dead, lol

If its the 12volts then problem is in the relay activation assuming fuse 13(30amp) is OK
You can have someone turn climate control switch OFF then to any other setting and you should feel the relay "click" or hear it "click"

If no Ground then could be the ground inside cab for speed switch or the speed switch itself


EDIT: One thing I forgot to mention is that the cab fuse box is inside the SJB(smart junction box) it has several multi wire connectors, and these connection are know for getting corrosion inside, just need to be cleaned

There is an article here that shows SJB and how to remove these connector to check them: https://www.therangerstation.com/tech_library/short_burst_horn_mod.shtml

You just pull the levers up and it disconnects the connector, then they can be removed for inspection
Connector numbering here: https://ricksfreeautorepairadvice.com/wp-content/uploads/2018/05/2007-Ford-Ranger-Fuse-Diagram-Smart-Junction-Box-3_0-4_0.jpg

Your fuse 27 runs to climate control thru C2280B, pins 18 and 22, as shown in diagram, pin 22 is 12v to power the blower relay thru the switch


AC-heat wiring diagram here