Firstly, the electrical connection of the blower motor has four wires: three live wires and one grounding wire. These are used to control the blower motor's speed settings 1, 2, and 3. To measure the resistance, you will need to measure the resistance of each of these three wires separately. Here's the detailed method:
1：Prepare a multimeter. Connect the black lead of the multimeter to the COM port and the red lead to the voltage port. Then, locate the four wires of the blower motor resistance below the storage box on the passenger side.
2：Place the black lead of the multimeter onto the blower motor's grounding wire, and the red lead onto one of the live wires. Check the reading on the multimeter's display to see the resistance value, and if needed, jot it down.
3：Subsequently, test the red lead on the other two live wires, repeating the previous step. If the resistance value displays as 0, it is possible that there's damage to the blower motor's resistance. In such a case, the car's blower motor might not be able to adjust its settings, and could only operate at its maximum speed setting. Replacing the resistance might be necessary.
Additionally, before measuring the resistance, ensure to turn off the car and disconnect the power. Otherwise, the measured resistance might have significant inaccuracies. If there's too much current, the multimeter might get burned out. There's also a risk of electric shock if not handled cautiously, jeopardizing personal safety. Therefore, always be careful when measuring.
