How replace blower motor controller in a Ford truck
Ford placed the blower motor controller behind the heater box on late model Ford F-series trucks equipped with variable speed blower motors. The blower motor controller is what provides the variable speeds by pulsing the power/ground to the motor based on the speed you choose. Think of this as a computerized version of the old fashioned blower motor resistor. The problem with Ford’s placement is that the shop manual calls for removing the heater box in order to replace the blower motor controller.
Removing the heater box in the larger E and F series trucks requires evacuating the AC system first and then removing the heater box. The flat rate guide shows times from 8.3 to as much as 10.5 hours. But there’s a way around this
Trick for removing blower motor controller in Ford trucks
The key to this trick is removing screws from the firewall side so you can move the heater box out far enough to wiggle the blower motor controller out from behind the heater box. Here’s the step by step
1) Remove the right front wheel well liner so you can access the three nuts from the heater box studs. Then remove the one bolt that’s near the drain tube.
2) Remove body control module (BCM) and the 4×4 module
3) Then remove the blower motor
4) Peel the carpet back towards the seat so you can access the are behind the heater box.
5) Use plastic pry bars to move the heater box into the passenger cabin a bit. Don’t pry too hard because the AC lines are still attached. Move it just enough to squeeze your hands behind.
6) Press down on the locking tab on the top of the blower motor controller so you can slide it towards the driver’s side until it passes the retainer tabs.
7) Reach inside the heater box from where the blower motor sat and roll the blower motor controller out through the blower motor hole. Roll the front down and slide it out
8) Disconnect the electric connector from the bum blower motor controller and connect to the new unit. Use the wiring harness and connector to help steer the new unit into place.
Posted on by Rick Muscoplat