Symptoms of bad blower motor relay - 1994 Jeep Grand Cherokee

94 CHEVY Silverado ????,heat/ac fan not blowing. K1500?????? Hear clicking when selecting l'm, SET high but not blowing! WITH AIR OR NO A/C? FIRST IS FUSES, MAKE SURE THE BLOWER FUSE IS NOT BLOWN.
EASY NO? CHECK ALL FUSES FIRST. ON ALL ELECTRICS FAILING OF ANY KIND.
BAD FUSE, BAD WIRINIG , BAD CONNECTIONS. OR EVEN BAD RELAYS TO THE BLOWER OR BAD SWITCH BLOW.
THE OLD CARS , HAD A SPEED BLOW , RESISTOR BLOCK
THAT FAILS ON ALL SPEEDS BUT HIGH, SO ITS NOT THAT.
OWN A VOLT METER????
HERE IT IS, ANY OF THIS CAN FAIL THIS OLD
WE USES A VOLTMETER TO FIND THE POINT OF FAILURE.
A SHORTED BLOWER MOTOR CAN BLOW LEFT SIDE TOP
FUSABLE LINK.RIGHT FUSE BLOWN MAKES THE CONTROLLER DEAD.

Check the AC fan relay
Symptoms Of A Defective Blower Motor Relay
The blower motor relay's job is to basically bypass the current that passes thru' blower motor resistor and deliver it directly to the blower motor. With the blower motor getting full battery current, it'll run in HI speed.

The most common symptom you'll see, when the blower motor relay fails in your Chevy S10 (GMC S15), is that the blower motor will not run in HI speed (but will run in LO, M1, and M2 speeds).

In some cases, the blower motor will fail and the blower motor will not run in HI but you'll have all of the other speeds working.

https://easyautodiagnostics.com/gm/2.8L/blower-motor-relay-multimeter-test-1

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CHECK SEE IF POWER GOING TO BLOWER MOTOR IF YES BLOWER MOTOR EITHER BAD OR HAS POOR GROUND SHORT IN WIRING CONNECTOR GOING TO BLOWER MOTOR AND RESISTOR.IF NO POWER GOING TO BLOWER MOTOR CHECK BLOWER MOTOR 30 AMP FUSE OR RELAY.IF BLOWER MOTOR OKAY AND FUSE RELAY OKAY THE AC AND HEATER CONTROL SWITCH COULD BE BAD.

COULD HAVE CORROSION INSIDE FUSE AND RELAY BOX CAUSING POOR CONTACT IN ELECTRICAL CIRCUITS. REMOVE FUSE AND RELAYS TO CONTROL CIRCUITS SPRAY A LITTLE ELECTRONIC CLEANER ALLOW IT TO DRY.CHECK BLOWER MOTOR RELAY IT COULD BE BAD OR BLOWER MOTOR RESISTOR BAD HOT BLOWER MOTOR TO SEE IF BLOWER WORK IF NO YOU HAVE FAULTY BLOWER MOTOR. IF BLOWER MOTOR WORKS WHEN YOU HOT WIRE BLOWER MOTOR CONTROL SWITCH COULD BE BAD.RADIO AND POWER PROBLEM COULD BE IN THE FRONT CONTROL MODULE IF CLEANING OUT CONTACT WITH ELECTRONIC CLEANER.DEALERSHIP HAS TO CHECK IT OUT.

CHECK BLOWER MOTOR RELAY ALSO, AND USE A TEST LIGHT TO SEE IF POWER GOING TO BLOWER MOTOR, IF YES BLOWER MOTOR FAULTY.IF NO POWER GOING TO BLOWER MOTOR AND FUSE AND RELAY OKAY CONTROL SWITCH COULD BE BAD,A RESISTOR BAD MOST OF THE TIME IF YOU DONT HAVE BUT A FEW FAN BLOWER CONTROL SPEEDS.

why not post the symptoms.? (all, not just dead) on all speeds?
the front just unscrews. its not hard, at all. nor worth 500 bucks.
but was that $450 for motor and $50 install? cant guess that ...

did you check all fuses first (in all fuse boxes , not just one)?????
FRONT OR REAR system? wow, with not symptoms i cant guess.
blow dead on HIIGH speed,
is it manual option or climate control HVAC option?
ATC or MTC systems (a means auto, m = manual)
did you replace the blower resistor first, if low speed fails.
did the hot wire test on blower fail, , ? do say this, as wasting a non good blower, is "over the top"

ill guess, front

1. Disconnect the negative battery cable.
2. Remove the instrument panel silencer from the passenger side of the instrument panel.
3. Remove the glove box from the instrument panel.
4. Disconnect the blower motor wire harness connector from the blower motor power module or resistor, depending on how equipped.
5. Remove the three screws that secure the blower motor to the HVAC housing.
6. Remove the blower motor from the HVAC housing.

rear is 16 steps. so..............................

all answers by me are USA cars, (usa forum it is)
and non Diesel, yes, its diffr.

now things that cause (hot wire to blower passes my tests)
failures of blower

1. blower relay bad,
2. input to relay wrong.
3. fuse blown PDC #1 F1.
4. A/c controller not commanding blow. there are 2 of these. modules.
5. lots more but i need your unstated facts first. all of them.

all this and more is in the FSM book or at alldata.com diy for $15

order
Fuse 1 good , use a scan tool yet, to see if there are errors>?

Relay PDC relay blower motor front has 12vdc on in 87
ill pretend MTC, system
the 12vdc above goes to the blower, pin 1, is it>?
then the controller grounds pin 2 of blower on high
does it 0v? there? , it does so via ground G200.
if not its bad or the switch to it is bad.
the resistor block does not kill HIGH speed ever. cant. do that.
so is controller, or its switch bad, if not 0v here.
(keep in mind, my hot wire test passes on the blower )O


if 12vdc is at pin 1 on motor
you can jumper pin 2 to ground, fan will blow on
high, if not blower is bad (front)
it if blows now then the controller is bad or inputs wrong to it.
simple huh?

You have a blower motor relay or a blower motor resister that could be bad.The relay is part # 1R2122 $20.79 at rockauto.com. You could jump the relay to see if that's your problem. The Resister is # RU474 $42.89. I would start with the relay. Your switch could also be bad. A simple 12V circuit tester will tell you if you are getting power to the relay terminals.

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?

I am assuming you are asking about the Blower Fan and not the Radiator Fan?
The Blower Fan is located below the Passenger side Dash. It is inside the black Duct work.
May I ask what the problem is?
Is the Blower working or only working on High? If only on High then the Blower Motor is fine and the Blower Motor Resistor that controls the Low to High speeds is bad. This is located behind the Glove Box in the Dash and on the firewall. Remove the Glove Box to access. It is approximately 3 1/2 inches by 1 1/2 inches and has 3 to 4 wires going into it.
There is also a Front Blower Motor Relay located in the Relays and Fuses.
Before replacing the Blower Motor, get back with me (for free) and let me know. This may save you alot of money in the long run, saving you from purchasing parts you may not need!
Let me know if this helped, and let me know what the problems (symptoms/signs) are.
Contact me in the Comment Section of your Posted problem.

Behind the vacuum heater controls in the dash, they lead to a relay mounted there. That was the relay that was bad on my Dodge. It was a digital readout one.