spudzy

I've researched the threads here for the past few days and can't seem to find one that duplicates my problem exactly, so I thought I'd start a new thread.
I have a '96 Cherokee right-hand-drive. The other day I had the A/C on and the blower motor either on high or medium. Suddenly I heard a small "tick" and the blower stopped completely, along with the compressor. The "tick" was apparently the fuse blowing, as there is now a blown 30 amp fuse in the panel (inside the vehicle). If I replace the fuse and have the heater/AC control switch in the "OFF" position, the fuse is fine. As soon as I put the switch into ANY position other than "OFF", the fuse blows. I can turn off the vehicle, put the control switch to "HEAT" (a position that does not utilize the compressor), start the vehicle and the fuse will blow. This tells me that the problem is not the compressor. I checked the relays in the power distribution center under the hood and even swapped out the one for the A/C clutch but that did nothing. I'm just wondering where to start here. Can I safely assume that the blower motor AND compressor are controlled by the same 30 amp fuse? Unfortunately, my US owner's manual does not seem to jive with the fuse panel when it comes to the fuse diagram. Do you think I should remove the heater/AC control panel & switch first? Any suggestions are much appreciated. Thanks!

Radi

I'd start by looking at the plug for the blower motor, they overheat. Might have a short down there.

spudzy

Thanks Radi. I unplugged the blower motor connector but the fuse continues to blow. I have a feeling this could take a lot of "wire examination" over the next several days...

freegdr

Unplug blower does it still pop ?

spudzy

Yes...the fuse still blows even after unplugging the blower motor.

freegdr

Ok its not the blower then. Can you unplug compressor and try again after that id check the fAn switch in dash.

spudzy

I'll probably go right to the fan switch assembly in the dash next. The compressor plug is very difficult to get to on my Cherokee. I'm not sure if this is due to it being a right hand drive or not, but the power steering pump is directly above it and it is all but impossible to access the compressor connector. I really can't see that being the issue anyway, because the fuse blows even when the selector is placed in positions that do not require the compressor to kick in ("Heat", "Vent", etc.). The only way the fuse doesn't blow is when that selector is in the "OFF" position.

The_ocho

I would check out your selector switch thing in the dash. All of the power for the blower runs trough the selector switch and then trough the fan speed switch then down to the resistor and then to the motor. I know on mine I had a problem with the fan being intermittent turns out it wasnt the fan but the whole HVAC system being interment because the selector switch will not send power to any component unless its in a position other than off. in my case it was a loose solder joint in the switch its self. there could be a short in there that is popping your fuse


You can see in the attached diagram that the power runs from the fuse to the "heat mode selector switch" which is the mode swithch for AC,heat, vent, defrost. etc. that is where i would start



A thread with alot of usefull info even though its about the resistor

definitive-blower-motor-blown-melted-resistor-switch-wire-fix-

spudzy

Thanks much for the diagram! I'm going to go over that switch assembly this week with a fine tooth comb.

freegdr

Ac clutch kicks on in all positions ,but if Ac plugs a pain deff go to switch.

spudzy

I have two '96 Jeep Cherokees and can honestly say that I don't believe the A/C clutch kicks on in all positions of the control switch. I have yet to hear it ever kick on if the switch is in "Heat" or "Vent" mode. Why would it? But thanks for the tip....I plan on checking the control unit in the dash next.

spudzy

Finally got around to pulling the control unit on the dash yesterday. I got lucky. In an effort to more easily remove the control assembly, I also removed my after-market stereo receiver. Shining the light into the now wide open dash immediately directed me to a yellow wire with a brown stripe where the insulation had been cut through by what must have been the back edge of the stereo receiver bracket. This wire was in the harness that plugged directly into the back of the heater/AC control assembly. The compressor and blower kicked in as soon as I removed the stereo. Taped up the wire and made sure it was out of the way this time....reinstalled everything and all is running as good as new. I'm actually surprised that it took over 3 years for that bracket to wear through the insulation to the point to actually create the short.