Turn the ignition switch ON.
Manually operate the control switch and measure the voltage of the blower motor.
Select the control switch to raise the voltage until high speed.
Fan Speed | Motor Voltage (V) | |
Manual Fan Speed | Auto Fan Speed | |
1 | 3.4 | Max. 4.5 |
2 | 4.6 | 4.5 ~ 5.5 |
3 | 5.9 | 5.5 ~ 6.7 |
4 | 7.2 | 6.7 ~ 7.7 |
5 | 8.3 | 7.7 ~ 8.9 |
6 | 9.5 | 8.9 ~ 10.1 |
7 | 11.3 | 10.1 ~ 11.3 |
8 | B+ | |
* Manual Fan Speed : 3.4V ~ B+
* Auto Fan Speed : 4.0V ~ B+
If the measured voltage is not within specification, substitute with a known-good power mosfet and check for proper operation.
Replace the power mosfet if it is proved that there is a problem with it.
Disconnect the negative (-) battery terminal.
Disconnect the power mosfet connector (A) and then remove the power mosfet (B) after loosening the mounting screws.
Install in the reverse order of removal.
