How to diagnose a blower motor failure?

How to diagnose a blower motor failure?

A less common cause is insufficient voltage to the blower.” The first step in diagnosing blower motor failure is to check to see if there is demand for the blower.

Why is the blower motor running at a low speed?

Be careful, on some vehicles when the engine is running the interior fan is in constant operation at a low speed. GM called this astro ventilation. This is to provide an ample supply of fresh air in the interior compartment even when no climate control mode is selected.

What does it mean when a blower motor resistor fails?

In our case the ohmmeter shows open circuit, which means the resistor has failed. Sometimes, a blower motor resistor might fail due to problems with the blower motor itself. This means after replacing the blower motor resistor, check if the blower motor runs freely and doesn’t make any noise.

How to test an inducer motor at high speed?

Move test switch SW-6 into the “On” position to initiate the component diagnostics. Allow the microprocessor to complete the diagnostic procedure for the inducer motor. This includes powering up the inducer motor, testing operation at low speed for 20 seconds, testing operation at high speed for 20 seconds then powering down.

A less common cause is insufficient voltage to the blower.” The first step in diagnosing blower motor failure is to check to see if there is demand for the blower.

Be careful, on some vehicles when the engine is running the interior fan is in constant operation at a low speed. GM called this astro ventilation. This is to provide an ample supply of fresh air in the interior compartment even when no climate control mode is selected.

What causes a bad or failing blower motor relay?

Blown fuses. One of the first symptoms of a bad or failing AC blower motor relay is a blown AC blower motor relay circuit fuse. 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…

What’s the best way to check the power of a blower?

“Measure the supply voltage to the blower as it’s running to be sure there is adequate power supplied. Measure the current draw when complete to make sure it’s within proper parameters. Don’t just replace [the motor] and run — check things over thoroughly. Tension the belt properly, if there is one.”