Most car manufacturers use a series of resistors to make the heater blower motor run at different speeds. And when one or more of these resistors burn out, you’re usually left with only one heater blower motor speed—high. The resistor module is easy and inexpensive to replace.
How do I know if my blower motor switch is bad?
Another symptom of a bad or failing blower motor switch is a switch that is stuck, or frequently gets stuck. If the switch or any of its contacts becomes damaged, this may cause the switch to jam, or get stuck when you trying to change the setting.
How do you test a Ford blower motor resistor?
Place one lead of the Ohmmeter on terminal 1 of the resistor. Place the other lead on terminal 2 and check against specifications. If this circuit is open, showing infinity on the Ohmmeter, the blower resistor must be replaced. Move the lead from terminal 2 to terminal 3 and check this reading against specifications.
Why does my air only work on high?
When a blower resistor fails, the highest fan speed usually is the only one that still works because it essentially bypasses the resistor and receives the maximum amount of voltage. When the resistor is working, it reduces the amount of voltage going to the lower fan speeds, so the fan runs slower.
How do you test a fan blower switch?
Test the switch. Plug the connector back in to the blower motor, and then trace the wire harness back to the connector closest to the blower motor switch, usually located under the dash. Disconnect the connector and set the multimeter to ohms.
Where is the blower resistor located?
It’s located inside the dash, often on the opposite side of the steering wheel or inside the engine compartment on the firewall. A blower motor resistor or a blower motor control module is the part that controls the speed of the blower motor.
Why does my AC not work at high speeds?
The A/C thermal expansion valve (TXV) most likely is the cause of the A/C system freezing up at higher engine or vehicle speeds. The A/C system should be performance tested and checked for pressures to make sure the system has enough refrigerant or the TXV is the cause of the problems.
Do all blower motors have a reset button?
All furnaces are equipped with a reset button. They are generally red or yellow and are located inside the blower compartment. The reset button is a safety feature that will shut down the furnace when a problem is detected, often a hot or overheating furnace, before it trips the circuit breaker.
How can you tell if a fan relay is bad?
Symptoms of a Bad or Failing Cooling Fan Relay
- Engine running hot. One of the first symptoms commonly associated with a bad or failing cooling fan relay is an engine that runs hot or overheats.
- Cooling fans do not function.
- Cooling fans stay on at all times.
Why is the 2004 Ford F150 blower motor not working?
The 2004-2014 Ford F-150 with manual temperature and fan controls may have problems with the the blower motor only blowing air on certain settings. Most commonly the fan will only run on the highest setting. This is a well documented problem, and is caused by a failing blower motor resistor.
Where is the blower motor resistor on a Ford F150?
The resistor is normally found behind the glove box, next to the blower motor. The average cost for a Ford F-150 Blower Motor Resistor Replacement is between $78 -$94. Learn More Fan only works on setting number 3.
Why does my fan only run on the highest setting?
Most commonly the fan will only run on the highest setting. This is a well documented problem, and is caused by a failing blower motor resistor. Correcting the problem is straight forward, and requires replacement of the small resistor. The resistor is normally found behind the glove box, next to the blower motor.
How much does it cost to fix a Ford F150 blower?
FORD F150 BLOWER RESISTOR 1997-2003 FIX! Only blows on high – $20 (Short version) – MECHANICAL KID – YouTube
