Why does my fan not work in high setting?

Why does my fan not work in high setting?

High (4), usually a seperate circuit that by passes the resistor and has a relay for higher current flow required in the high setting The most common cause of two or more speeds not working is the resistor, because if resistor two burns out it will affect speeds 1 and 2 but not 3 and 4.

Why is my AC heater fan not working?

This sounds more like a problem with high speed fan relay. On the low speeds, the fan relay routes the voltage thru the resistor block. When you switch to high fan speed, the relay switches over to supply full voltage from the battery to the fan motor.

How do you turn on a high speed heater fan?

Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high. The fan should be blowing on high, now wiggle the connector one more time the fan should stay on without interruption.

Why does my GMC heater not work on high?

1997 GMC C1500 Heater/AC blower will not work on HIGH. I have replaced the black BOSCH relay behind the glovebox, the blower RESISTOR and the blower MOTOR and still cannot get the blower to work on HIGH. I remember in older model years of GMC’s and Chevys that their was a high speed blower relay that caused this issue.

This sounds more like a problem with high speed fan relay. On the low speeds, the fan relay routes the voltage thru the resistor block. When you switch to high fan speed, the relay switches over to supply full voltage from the battery to the fan motor.

Now pull the zip tie tight and cut the long end off with side cutters. Now reconnect your battery and turn your ignition switch back on and fan speed switch on high. The fan should be blowing on high, now wiggle the connector one more time the fan should stay on without interruption.

Can a blower fan only work on high speed?

Blower Motor Fan Only Works On High Speed? Plus – Tips To Prevent Repeat Failures! If playback doesn’t begin shortly, try restarting your device. Diagnostic training videos and content hosted by ASE Master and L1 Certified Technicians.

1997 GMC C1500 Heater/AC blower will not work on HIGH. I have replaced the black BOSCH relay behind the glovebox, the blower RESISTOR and the blower MOTOR and still cannot get the blower to work on HIGH. I remember in older model years of GMC’s and Chevys that their was a high speed blower relay that caused this issue.