92 ISUZU PICKUP BLOWER MOTOR DOES NOT WORK, THE MOTOR TEST GOOD, ALL FUSES ARE GOOD, RESISTOR IS NEW. HAVE POWER AT PLUG BUT IT FLUTTERS THE TEST LIGHT. I NOTICED WHEN I UNPLUGGED A BAD DOOR CHIME MODULE THE POWER AT THE BLOWER MOTOR AND RESISTOR SWITCH GOES OUT AS WELL. ARE THESE CONNECTED IN SERIES SOME HOW?

No VIN or country told nor any engine.
what model pickup is it, NOT TOLD ! wow!
sorry the engine can dictate fuse box wiring vastly


you have meter ? DMM"?
finding cause is easy with meter (volts)
not guessing all parts,
and schematic, of the blower
first off the blower is just a 12vdc motor.
and can be hotwire or even bench tested.
very few 33yo cars run now, and is frankly amazing.
so when did blower last work, last decade?
my online 1990 service manual crashes on the HVAC pages. (sad face)
here is the path on most.
battery not dead, engine starts and runs (not told)
fuses good, for sure blower fuse.(HVAC)
then key switch is good and blower controls get power to the blower relay and to the controls blower speed and mode switch.
we use a meter to trace this path, to the switch
blower tested on HIGH.
if dead voltage here we test backwards path above
if not dead here, we make sure 12vdc make it to resistor block, if yes, then to blower motor.
if it fails at any test the problem is backwards path dead.
some versions of this PU, have 3 fuse blocks
and #3 is heater. 2 fuses and 3 relays there
a real service manual is always best.
buy one used off Ebay,
canada model wired different than USA if is USA?
FB3 is right side (LHD) USA cars dash. not left.
FB2 is engine bad
FB1 is left dash.(LHD drive)
FB= fuse box.


USA only 91,.

I would change the blower is done.

sound's like a earthing problem , try a continuity test from blower LIVE to chassis , if get continuity then def got a wiring problem , very difficult to diagnose without seeing vehicle , get a auto electrician

What is near the motor? This isnt working on HIGH. So its not a resistor. If that is what you are talking about? High isnt connected to a resistor. Its direct power so what would changing the resistor do if the only possible problems are fuse, relay or switch? If it worked on HIGH and not setting one through three then yes it would be the resistor on the ac blower motor if it is still powering on when tested on the low settings.

either have a fuse blown, or you need a resistor pack. it's located in the heater box next to the blower motor.

Did you find out a solution to your problem? I have a 1996 trooper that is showing most of the same symptoms that you have. I'm curious as to your fix. Was it simply a bad ground?

if fuses are good, check for power at blower motor, when truck is running and a/c on. the resistor and the switch provide ground, so the blue/white wire should have power, and the blue/black wire should have NO power, if it does have power, then most likely the resistor is bad. if it has no power and the motor doesnt run, the motor is bad.

The resistors are in circuit only on the lower fan speed settings.
On the highest speed setting, power is switched directly to the fan motor.
Check fan power supply fuses,
Check power is available to the fan when high speed selected.
If all above OK, apply power directly to the motor to verify fan motor runs- if it doesn't the motor may need replacement/repair.

You can test the blower motor by connecting a positive and negetive wire directly to the 2 terminals on the motor.
As far as the resistor goes. If the blower motor only works on high fan speed then the resistor is bad. If it works on all speeds except high, then the relay is bad. Good luck. Hope this helps.

Check the ground, the resistors are accully resisnting the Negitive Current.