Check the Fuse:
Locate the fuse box and check the fuse that corresponds to the heater fan. If the fuse is blown, replace it with a new one of the same amperage.
Inspect the Blower Motor:
The blower motor is responsible for the actual movement of air. It could be faulty or worn out. Try accessing the blower motor, typically located under the dashboard on the passenger side, and check for any signs of damage or wear. You may need to replace the blower motor if it's not functioning.
Watch this video to see how to replace blower motor in S10
Test the Blower Motor Resistor:
The blower motor resistor regulates the fan speed. If it's faulty, the fan may not work. Use a multimeter to test the continuity of the resistor. If there's no continuity, it may need to be replaced.
Examine the Heater Controls:
Check the heater controls on the dashboard. If there are issues with the control panel or the wiring connecting it to the blower motor, it could result in a lack of power to the fan. Ensure that all connections are secure and free from damage.
Inspect Wiring and Connectors:
Inspect the wiring and connectors associated with the heater fan. Look for loose or damaged wires. If you find any issues, repair or replace the affected wiring.
Check the Blower Motor Relay:
The blower motor relay controls the power to the blower motor. Test the relay or replace it if necessary.
Verify Grounds:
Ensure that the blower motor and associated components have a good ground connection. Poor grounds can lead to malfunctions.
Consider the Blower Motor Switch:
The switch on the dashboard that controls the fan speed may be faulty. If other components check out, the switch could be the culprit.
