1999 jeep wangler blower good new switch new resistor still dont work

There are two fuses a 40 amp in the power distribution center and a 10 amp in the fuse block. Are they good?

This is a ground side controlled system meaning the switch provides ground instead of power. With everthing plugged in there should be power on all the wires coming out of the blower motor resistor ( brown w/ tan, Light Blue, Light green w/ black, and tan wires). If you ground any of those wires the blower motor should run. If it does check the dark green wire at the HVAC control head. Backprobe that wire with it plugged in if there is power than either the control head is bad ( the mode switch has the final say in the path to ground for the blower motor. When the mode switch is in the off position the blower will not work. When it is in any other position (vent/floor/defrost) it allows the path to ground for the blower motor to be complete.

The last thing to check is to make sure the black wire coming out of the control head has a good ground. That is the final path to ground for the blower motor.

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If you bypass the resistor pack and connect the motor directly to the fused 12v supply then the fan should run at maximum speed. If so, it's the resistor pack that's blown: a very common fault on a huge number of makes and models.

You probably do need a new switch, but check all the connections between the switch and the resistor pack first.
(These blower motor supply wires carry heavy current - commonly, a loose or poor connection will overheat and fail).

the blower motor resistor is bad replace it and it will work good as new the resistor is located in the same heater box as the blower motor mounted on the outside of the heater box follow the wirring from the blower motor to find it or just simply buy the part and match it up

Check the fan/blower switch. Mine shorted-out and blower did not work for years but it was merely a switch problem.

if the motor wasn't making any sounds then i say change the resistor, because motors don't go bad just like that.

blower motor resister has burnt out also check wiring going to your blower motor resistor these must have a good tight connection or they will burn if any sighns of being hot change the complete wiring pig tail to your blower resistor

HOT WIRE BLOWER MOTOR IF IT WORKS PROBLEM IN THE BLOWER RELAY AND RESISTOR.IF BLOWER DONT WORK REPLACE IT.

Run a new wire to the motor from the switch this will do 2 things for you. It will tell you if your switch is still good, and if it works you just fixed your problem.

tepfy

Could be a bad connection between the battery and starter. Starter solenoid, or neutral safety switch if it is standard transmission.
Check for power at the solenoid.
Lone99star

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