Use additional wires to supply voltage from the battery to the contacts and the fan motor connector. If the fan motor rotates, it is working properly.
Sequentially switch on the fan operating modes AUTO → LOW → HIGH → AUTO and measure the voltage at contacts 1 and 2 of the connector.
Fan | Voltage, V |
| First speed | 3,8 |
| Second speed | 5,3 |
| Third speed | 6,7 |
| Fourth speed | 8,1 |
| Fifth speed | 9,5 |
| Sixth speed | 10,6 |
| Seventh speed | 13,5 |