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kyle_inreallife
December 6th, 2017, 14:09
87 xj Wagoneer limited

I want to do what I can before taking off the dash. The levers on the hvac controls feel like they're mechanically actuating the switches so I don't think it's disconnected. Blower for vents/heat and ac compressor both don't turn on. I was thinking blower motor or connection but i don't think that explains no AC sooooooo.....where do I start?


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ehall
December 6th, 2017, 14:29
One of the more common failures is the speed dial on the HVAC control unit, the dial is known to melt and short the contacts. Not a hard repair but before you do that you should verify the fuses and motor. There is a blower motor fuse either under the hood or under the dash, I can't recall. You can also use some wire to run direct battery power to the blower motor and verify that its not seized.

Ecomike
December 6th, 2017, 17:02
It could be one or more of the following.

The blower fuse under the dash drivers side..
The wire to the Ignition switch that powers the Blower and radio and WS Wipers.
The ignition switch (contacts that power the blower etc)
The AC blower speed switch.
The speed resistor pack that blower selector switch powers to drop the blower speed it is under the dash on the passenger side
And the blower motor itself.
10 years ago I had to replace them all on an 85 and many of them on the 87, with in about three years as one going bad stresses them all into overheating.

The Wagoneer is super rare and very valuable now!!!

If yours is a manual transmission check the fuse and fuse holder as the master cylinder likes to leak brake fluid from the Transmission MS onto it and it ruins the fuse contacts in the fuse block.

On my 87 Wagoneer, I replaced the wires from the battery to the fuse to the ignitions witch, with 10 gauge wire (stock is 14 gauge BS) and a 30 amp dash toggle switch and 30 am breaker (fuse). It also runs the electric seats and windows, and radio and windshield wiper and turn signals on one piss ant 14 gauge wire.

kyle_inreallife
December 6th, 2017, 19:32
It could be one or more of the following.

The blower fuse under the dash drivers side..
The wire to the Ignition switch that powers the Blower and radio and WS Wipers.
The ignition switch (contacts that power the blower etc)
The AC blower speed switch.
The speed resistor pack that blower selector switch powers to drop the blower speed it is under the dash on the passenger side
And the blower motor itself.
10 years ago I had to replace them all on an 85 and many of them on the 87, with in about three years as one going bad stresses them all into overheating.

The Wagoneer is super rare and very valuable now!!!

If yours is a manual transmission check the fuse and fuse holder as the master cylinder likes to leak brake fluid from the Transmission MS onto it and it ruins the fuse contacts in the fuse block.

On my 87 Wagoneer, I replaced the wires from the battery to the fuse to the ignitions witch, with 10 gauge wire (stock is 14 gauge BS) and a 30 amp dash toggle switch and 30 am breaker (fuse). It also runs the electric seats and windows, and radio and windshield wiper and turn signals on one piss ant 14 gauge wire.



Extremely helpful! Would you mind if I pm'd you as I get into it?


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Ecomike
December 7th, 2017, 04:13
PM is fine, no problem, but sharing the repair path publicly serves others with the same problem in the future.

kyle_inreallife
December 7th, 2017, 06:58
Fair enough! Will follow up this weekend when I get into it.


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old_man
December 8th, 2017, 04:33
If you can hear the motor run in the high mode only then it is probably the resistor pack. If you can hear the motor in all speeds, check to make sure it isn't coming out the defrosters all the time. If so you have a vacuum leak. If it simply does not run at all, check the fuse, then measure voltage on the motor directly. If you have voltage there, replace the fan.

Happy Hunting.

cruiser54
December 9th, 2017, 04:53
Here's something you should do as a preventative measure while you're working on it.

http://cruiser54.com/?p=211

BattlebornXJ
April 18th, 2018, 18:55
Had the same problem. Have a 2000 XJ. Suddenly fan not blowing air from vents. Passenger kick panel fuse #25 good. 40A fuse under hood in Power distribution box good. Switch has continuity. A/C clutch engages when A/C is selected. Connected fan motor directly to 12V, fan motor good. Fan motor connector getting 12V only when fan switch is in position 1, and selector switch is in OFF position. Resistor pack has continuity from all spades. WTF?
Well, Chrysler in its infinite wisdom put the relay for the blower motor under the dash directly behind the glove compartment. Tested the relay and guess what? Yep, that was the problem. $9.00 at Autozone. Remove the three screws from the hinge at the bottom of the glove compartmrent door, release the latch and it pops right off. Spent hours diagnosing, and the fix took 5 minutes. WHY didn't Chrysler just put the relay in the under hood box with the others?

Ecomike
April 21st, 2018, 11:36
Earlier Jeeps had no relay, and would burn up the speed switch, Ignition switch, resistor pack, and fuse and contacts under driver side dash. The put the relay in to solve all those problems, and put it close the Blower and Resistor pack where large gauge wires need to be, to save on wire cost. That blower pulls a large amp load all the time. Car companies are not interested in make vehicles easy to service. Never have been

Had the same problem. Have a 2000 XJ. Suddenly fan not blowing air from vents. Passenger kick panel fuse #25 good. 40A fuse under hood in Power distribution box good. Switch has continuity. A/C clutch engages when A/C is selected. Connected fan motor directly to 12V, fan motor good. Fan motor connector getting 12V only when fan switch is in position 1, and selector switch is in OFF position. Resistor pack has continuity from all spades. WTF?
Well, Chrysler in its infinite wisdom put the relay for the blower motor under the dash directly behind the glove compartment. Tested the relay and guess what? Yep, that was the problem. $9.00 at Autozone. Remove the three screws from the hinge at the bottom of the glove compartmrent door, release the latch and it pops right off. Spent hours diagnosing, and the fix took 5 minutes. WHY didn't Chrysler just put the relay in the under hood box with the others?