usually the blower motor resistor pkg. located on or near the blower motor
Normally when some speeds work and others don't, the problem is a bad, Blower Motor Resistor Pack. You will find it somewhere near the blower motor.
If the blower motor randomly and intermittenly quits and does not work, chances are good the blower motor itself is faulty, if the blower motor does not work on all fan speeds from low through high, it most likely needs a blower motor resistor.
If you have no blower speeds at all check the fuse, then check the blower motor switch and electrical plug for a melt down situation, then check the blower motor itself.
If all speeds do not work, suspect the fuse, the switch, the switch connector or the blower motor. If only high speed works, suspect the blower motor speed resistor. If low speeds work and not high, suspect the blower motor relay.
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.
More than likely the blower motor resistor pack is bad, although it can also be the switch itself.
if all speeds do not work id say is a fuse, but if you just dropped one or two speeds. replace the blower motor resister. sells for $60.00 at the dealer.
Blower wont work on all 5 speeds, usually the lower speeds tend to go first.
If a blower motor resister is bad the fan won't work at all or will only work on certain speeds. And you will see on the resistor a missing link where it burnt out kind of like in a light bulb
the reason blower does not work on all speeds, is the fan blower motor resistor. The resistor is a 4-5 step series circuit, 1 resistor is added for each reduction in speed. If one burns out then so will all speeds below it. The "high" circuit usually has a separate fuse and bypasses the resistor altogether.
Sounds like a bad blower motor resistor block.
The blower motor resistor that sits behind the blower motor itself all the way against the firewall.