It depends on what kind of car you have. Some have a relay center.
If the blower works on slower speeds only I would suspect the high speed blower motor relay (under the hood in the power distribution box) or the switch itself. The blower speed resistor is working if all the slower speeds work.
possibly a high speed blower relay. If the the ac works on all speeds but high, this is my bet. You should be able to pick up a replacement relay at most parts stores.
One would be for the A/C compressor clutch relay, another would be the high speed function for the HVAC blower motor, not sure about the other two.
If you only have high speed I would blame the blower speed resister. If you have no speeds and the fuse is good, I would blame the blower motor or the switch.
There should be a smaller plastic box behind the fuse box in the engine compartment. There you will find the high speed fan relay as well as the low speed fan relay.Good Luck
Blower motor control?
The high speed blower relay is located on the engine bulkhead bracket next to the blower motor. === ===
A typical blower motor relay only operates the high speed function.
The blower motor fuse protects the blower motor electrical circuit. The blower motor relay operates only the high speed function of the blower motor. The blower motor speed resistor operates the lower speed functions of the blower motor.
A fan or cooler relay is used in electrical furnace to change the blower speed to the blank speed for cooling
The relay for only the high speed blower function is located in the fuse and relay center under the hood. The resistor for the blower motor lower speeds is located under the hood, passenger side, on the firewall close to the blower motor.
Only for the high speed. The lower speeds are controlled with the use of a blower motor speed resistor.
if your blower is working on low and medium speed then it's not a fuse it is the blower switch
The blower motor relay only operates the high speed function. That relay would be in the fuse/relay center under the hood.
The blower motor high speed relay is located under the hood, on the passenger side firewall close to the blower motor. The blower motor speed resistor is also located in that same area.
Sorry but it is not a relay. It is a power transistor voltage regulator board located on the center area of the firewall and controlled by the Climate control computor. I have an 89 with low speed blower working only. I tapped into the module wire connection to a small switch I installed under the dash for high speed operations.
Yes, there is a high speed relay and it should be in the fuse/relay center under the hood.