Why is my AC fan always on?

Why is my AC fan always on?

The thermostat is faulty. If the fan and the cooling system are running when they shouldn’t, there’s a chance the thermostat may require a replacement. If only the fan is running when the AC isn’t, there may be a faulty relay switch stopping the settings you enter on the thermostat from being communicated to the fan.

Where is the blower control switch on the dashboard?

The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.

What happens when a blower motor relay wears out?

Without it, the AC system will not be able to circulate any heated or cooled air. The blower motor relay controls the current used to power the blower motor, and is subject to the constant on and off switching. Over time, it can eventually wear out.

What causes a fuse to blow on a blower motor?

If the blower motor relay develops any sort of problem that hinders its ability to properly limit and distribute power, it may cause the blower motor fuse to blow. Any sort of electrical spikes or excessive current from a bad relay will blow the fuse and cut power in order to protect the system.

Where is the regulator on a Mercedes fan blower?

The Mercedes Benz fan blower motor regulator is a series of resisters in a printed circuit board about 2-inches square located right next to the blower motor.

The blower control switch on the dashboard controls the circuit flow of the blower motor to adjust the voltage from low, to medium, to medium-high, to high. When on high, the circuit bypasses the blower resistor.

Where is the resister on a Mercedes Benz fan?

Just to the left of the blower motor, an electrical connector connected to a flat 1-inch-by-2-inch plate can be seen. This is the blower motor resister, which controls the fan speeds. Disconnect the multi-wire connector from the blower motor resister next to the blower motor. Start the car and turn the air conditioning on.

Where is the blower motor on a Honda Accord?

Locate the blower motor. The motor can be seen hanging down close to the passenger kick panel. Just to the left of the blower motor, an electrical connector connected to a flat 1-inch-by-2-inch plate can be seen. This is the blower motor resister, which controls the fan speeds.