2005 international 9400i blower control problem

Sounds like On/Off fan speed switch is bad.

 

When you have no speeds at all, it is either a bad blower or hvac control head or main wiring into it. Since you already replaced the blower, your options are limited. The blower speeds are powered differently through different breakers and relays, so usually a wire, relay or breaker problem only effects that one speed. So we need to see of the hvac control is working properly. With the system turned on, "Main Control" relay should be energized which sends power to terminal 30 of the "MED-HI" speed relay. If you remove the hvac control or unplug it from behind, you can check for power at the main connector that goes to the speed switch. Look for wire 75B, green in colour. Should have power there. This is your 12v into the switch. You can jump 75B to 75BH for med-low, 75N for med-hi and 75H for high speed. If you have no 12volts then check that main control relay and breaker F1-C, (20 amp)

 

Ok, this power comes from Main Control relay R5. See if it has power, if not check that F1-C breaker. If all that is fine, the Main control relay is triggered by the HVAC control panel, so it may be faulty after all. Check F9-D too.