1990 honda civic cabin heater fan has ceased blowing. all my fuses are intact....

[Mike G]

...Ideas on what to test next pls? The heater fan control that only used to work in positions 3 & 4 now has stopped working altogether. I have dismantled the fascia and took apart the switch and tested for juice and there wasn’t any, at the back of the switch is the wiring harness, which is something i dont wantt to tamper with.

 

[AL M]

Check the voltage through the harnes that connects the blower motor. The voltage should keep going up with the higher position on the switch. If no juice, then its a switch or wiring problem.

You can easily check the motor by connecting it directly to a 12v dc source.