New Topics › Forums › General Discussion › 1999 – 2002 Nissan Quest › Replaced Blower Motor and Resistor working just barely 2000 Quest › Reply To: Replaced Blower Motor and Resistor working just barely 2000 Quest
First, I am assuming that you are referring to the front blower. The speed is controlled by the resistor block. This confirms you have a MANUAL A/C control unit, not an automatic. Any difference in ohms of any of the resistors in the new block, compared to the original block, will alter speeds 1 to 3 of the new motor. Speed 4 of the motor is full speed. If the blower does not produce the same speed/flow of air, you are using the wrong fan/motor combination. Please confirm to me if you used original blower fan with new motor or replaced fan/motor combo.
Looking at the electrical diagram on page HA-148, in position 4 for the front fan, the blower motor is energized with full battery voltage. This means, the resistor block is not used for that speed setting. The block only controls lower speeds from 1 to 3.
If the motor failed by blowing out the main 20Amp fuses. The original motor is in short-circuit. That might also had blown out the internal fuse of the original resistor block. If this was the case, replace the motor, check the fuse of the resistor block and replace fuse if necessary. Use new motor with original resistor block.
If the motor failed in open-circuit, use new motor with original resistor block. Check internal fuse of original resistor block and replace if necessary.
Full procedure for diagnosing the front blower motor starts on page HA-166. With an ohm-meter, please check the resistance of each resistor in the block. Follow the terminal and ohms reference table that is located in manual HA page 171.
Let me know what results you have.