What is the purpose of a blower motor resistor?
The blower motor resistor is an electrical component that is a part of the vehicle's heating and air conditioning system. It is responsible for controlling the blower motor's fan speed. A failed blower motor resistor can cause issues with the operation of the entire heating and air conditioning system.
The fan speed can be changed either by switching the blower resistor resistance mechanically, using a rotating lever, or electronically by the air conditioning system. The change in resistance then limits the current through the motor, which dictates the speed at which the blower fan works.
- The blower motor is the component responsible for pushing air through the vents of your vehicle's heating and air conditioning systems. Without it, the AC system will not be able to circulate any heated or cooled air.
- Blend door actuators, also called HVAC actuators, control the position of the vents that control the flow of air into your vehicle's passenger area. The actuators are small electric motors that move the vent doors, mixing hot air with cold air to achieve the temperature that you desire.
- We'll use the terms supercharger and blower interchangeably. The centrifugal supercharger is very similar to a turbocharger, except the centrifugal supercharger is driven by a belt off the engine, while the turbocharger is driven by the force of the exhaust gases.
Several symptoms may point to a bad or failing thermo coolant fan switch.
- Engine overheating. Engines generate an enormous amount of heat and as a result are subjected to very large temperature swings if this switch does not operate effectively.
- Check Engine Light comes on.
- Broken or shorter signal wire.
- There are several common symptoms associated with a bad or failing thermostat that will alert you that service is due.
- Temperature gauge reading very high and engine overheating.
- Temperature changing erratically.
- Coolant leaks around the thermostat housing or under the vehicle.
- The Coolant Temperature sensor is critical to many PCM functions such as fuel injection, ignition timing, variable valve timing, and transmission shifting. The Coolant Temperature sensor is located in a coolant passage in the engine usually near the thermostat.
- Remove the wire from the temperature-sending unit located on the engine (typically a dark green wire). Then connect the wire to a good ground. You can do this by using a jumper wire. Check the gauge, if the needle points to “Hot”, replace the sending unit.
The average cost for a blower motor resistor replacement is between $83 and $150. Labor costs are estimated between $35 and $78 while parts are priced between $48 and $72. Estimate does not include taxes and fees.
- An engine does not actually "blow up." There are many types and causes of engine failure. The most catastrophic – and visual – is a broken connecting rod punching a hole in the block or crankcase. A connecting rod is the part that connects a piston, which is moving up and down very quickly, to the rotating crankshaft.
- The motion of that piston is what makes the crankshaft turn--and ultimately what makes the car move. The metal part that connects the piston to the crankshaft is called a "connecting rod." RAY: When you "throw a rod," it means that one of these rods has literally broken off. When that happens, one of two things occurs.
- An average connecting rod repair will cost anywhere from $2,500 and up. On some vehicles like a Subaru Forester, that can run $5,000 between parts and labor for an engine rebuild or beyond $6,000 for a whole new engine replacement.
Updated: 3rd December 2019