What to do if your blower motor only works on high speed?

What to do if your blower motor only works on high speed?

If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode. To repair the problem, simply replace the resistor block. It’s usually located in the ductwork (to keep the coils cool) below the glove box.

How do you troubleshoot a blower motor resistor?

This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time. Power supplied from the fuse panel passes through the switch to the blower resistor assembly.

What causes a blower fan to not work?

When this happens, you may notice that you will not feel anything blowing out of the vents at all. This may also cause the blower motor to work intermittently. A blower fan is connected to the negative battery terminal (also called ground) on one end and to the positive battery terminal through a blower motor resistor on the other end.

Where is the blower motor resistor on a Mazda 5?

In many cars it’s fairly easy; the blower motor is located behind the glove box and held by 3-4 screws. In others it might be located inside the dash (e;g Mazda 5) which makes replacement difficult. If you need a proper diagnostic procedure, we posted several links where you can access a service manual for your car for a subscription fee.

If your blower only operates on its highest speed, chances are you have the series type of blower motor resistor. This is the most common failure mode. To repair the problem, simply replace the resistor block. It’s usually located in the ductwork (to keep the coils cool) below the glove box.

When to replace a heater blower motor switch or relay?

When the motor gets old and tired it will draw more current through the wires than a new motor. It may still draw enough current to blow the fuse after it runs for a while. In that case, a motor replacement is in order. Step 1: Disconnect the battery. Put on your safety glasses and disconnect the battery at the negative cable.

This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time. Power supplied from the fuse panel passes through the switch to the blower resistor assembly.

What should I do if my heater blower fuse blows?

The repair involves installing factory updates to make the fuse panels equal to the task. Step 4: Replace the fuse. If the fuse is blown, replace it and then try the blower. If the fuse blows right away, your car may have a bad blower motor or some other problem in the system.

Why does my blower fan only work on one speed?

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

How can I tell if my blower speed switch is faulty?

Test for power at all the blower speeds by moving the blower speed switch through all positions. A faulty resistor loses power at different positions on the switch. High blower speed has direct power to the motor from the switch. If there is no power indicated on high blower speed, the problem is most likely the switch or the fuse.

by Lee Sallings. The most common symptom of a faulty blower motor resistor is a blower fan that only works on one speed, usually high. This can be annoying, but troubleshooting is easy. If you start at the blower motor, and check resistance in the circuit, you will find the problem in no time.

Test for power at all the blower speeds by moving the blower speed switch through all positions. A faulty resistor loses power at different positions on the switch. High blower speed has direct power to the motor from the switch. If there is no power indicated on high blower speed, the problem is most likely the switch or the fuse.

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