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SqueegieSteve
September 1st, 2010, 08:48
So ever since i bought the jeep the blower has only worked on '4' but last night it finally just all out stopped working. I didn't smell any burning or smoking so i don't thing i fried the blower motor,should i replace the resistor pack? If so where is it?
BNut if it was the resistor pack (which has been bad for a while) wouldn't it still work on '4'? THANKS!

SqueegieSteve
September 1st, 2010, 13:03
I just replaced the resistor but it's still not working... the blower fuse isnt blown either... anybody else have this prob?

OkieXJ
September 1st, 2010, 13:30
When is was working on '4' was it blowing really hard or was it barely blowing like it was set on 1? Did it stop working gradually or all at once? It sounds like it might be a switch issue to me.

FYI, you'll want to post the year of your Jeep etc. or else the veterans will jump on you.

Pelican
September 1st, 2010, 13:46
The blower motor does not have to burn or smoke to fail although it will often, if not usually, make various noises as the bearings go. Failing bearings are what usually cause the resistor pack to overheat and blow the thermal fuse that is a part of the pack. You need to put your meter across the original thermal fuse just to see if you have continuity--essentially 0 ohms resistance--to rule this out as part of the problem.

Next, or perhaps first, check the blower motor by briefly connecting a 12v source to the power leads in the engine compartment. You will find a plug near the motor. If the motor runs okay, you likely have a problem with the blower motor switch or its connector.

Edit: OkieXJ has good questions. I'm assuming a '97.

SqueegieSteve
September 1st, 2010, 15:06
Sorry it's a 98

Where is this plug in the engine compartment to test the blower motor out? could i just put power to the terminals at its fuse in the fuse box? I could probably just run two leads off the battery to it to test it right?

joe_peters
September 1st, 2010, 15:09
The blower motor does not have to burn or smoke to fail although it will often, if not usually, make various noises as the bearings go. Failing bearings are what usually cause the resistor pack to overheat and blow the thermal fuse that is a part of the pack. You need to put your meter across the original thermal fuse just to see if you have continuity--essentially 0 ohms resistance--to rule this out as part of the problem.

Next, or perhaps first, check the blower motor by briefly connecting a 12v source to the power leads in the engine compartment. You will find a plug near the motor. If the motor runs okay, you likely have a problem with the blower motor switch or its connector.

Edit: OkieXJ has good questions. I'm assuming a '97.

Agree. When the motor was only working on its highest setting meant that the resistor pack was burnt out. Now, with the motor inoperable, you have a motor/switch/harness issue.

Pelican
September 1st, 2010, 15:34
The problem with connecting to the fuse block is you are still running the current through the suspect components. You need to isolate the motor.

It will be nearly as easy to connect it directly in the engine compartment, at least on earlier models--not sure what is in the way on the '98. On the '93 the motor is behind the coolant overflow bottle and mounted to the firewall with three screws. I do not recall offhand if it is possible to access the plug without removing the bottle but it is not difficult in any event.

Someone familiar with the '98 will have to respond with details.

Snarky
September 1st, 2010, 16:59
Before you tare into it too much, i had the same problem with my 98. My high speed did not work, then after a while it just quit working on me. Just check behind the glove box for a relay that looks like a little black cube. That relay should be your blower motor relay. The glove box should come off and the relay will be right there.

My blower relay overheated, burnt the wires connecting to the relay and melted the plastic. The motor would not come on and my first assumption was the motor had died or the switch broke. If yours looks ok, check the relay with a meter, or just swap the relay from another accessory to make sure that its not the problem.

SqueegieSteve
September 1st, 2010, 17:01
it seems that the blower is mounted from inside the firewall... the connector must be behind there too. it looks like I'm gonna have to take off the glove box and some parts of the dash to get to it

SqueegieSteve
September 1st, 2010, 17:10
Before you tare into it too much, i had the same problem with my 98. My high speed did not work, then after a while it just quit working on me. Just check behind the glove box for a relay that looks like a little black cube. That relay should be your blower motor relay. The glove box should come off and the relay will be right there.

My blower relay overheated, burnt the wires connecting to the relay and melted the plastic. The motor would not come on and my first assumption was the motor had died or the switch broke. If yours looks ok, check the relay with a meter, or just swap the relay from another accessory to make sure that its not the problem.

Snarky i'll check that out. sounds to me liek its most likely.. it was really hot out when it blew

Snarky
September 1st, 2010, 17:14
Oh, and the Blower motor leads are accessible in the engine compartment. The blower motor is on the passenger side firewall. The a/c accumulator is in the way, so you cant pull the blower, but you can still reach the wires. The wires plug into the motor via a sta-kon type connection.

I would test the motor by applying 12v to the leads before you try to replace the motor. For testing the motor, you can cut the wires if your comfortable with crimping/soldering them back together. Then just hook the battery directly too it. It wont hurt the motor if you reverse the polarity, it will just spill the blower backwards.

SqueegieSteve
September 1st, 2010, 17:42
i just checked the relay... the wires weren't melted but i noticed that when i tried turning on the blower the relay still didn't switch... shouldnt that relay flip when i turn on the blower?

Snarky
September 1st, 2010, 18:02
Try swapping the relay with another one. Barrow a relay in your main fuse block under your hood. Grab the ABS one, you don't need it anyways :P

Pelican
September 1st, 2010, 18:31
The first thing you do if you are going to do anything with your XJ other than just sit and gaze adoringly at it, is order up five or six 40a or 50a relays to keep on hand. You will need them sooner or later. They are dirt cheap online (Parts Express/Del City etc.).

I know many go out to a yard and collect a handful but I generally like new for electrical stuff plus I don't have a yard anywhere near.

Just a thought.

SqueegieSteve
September 1st, 2010, 19:53
haha yea that's for sure..
i already switched it out and there's nothing wrong with it. i'll try to hardwire the motor next. If it's working then i'll check the switch, but how do i do that? Just use a multimeter (check continuity) on the terminals?

Snarky
September 1st, 2010, 20:24
yup, take it apart and verify that it works with a meter

Jeff-97XJ
September 1st, 2010, 20:31
yup, take it apart and verify that it works with a meter


If the blower motor needs replacing, it is no big deal. I bought a brand new import one for my '97 on ebay for 54.00. It only took 1/2 hour to install. Very easy job, hardest thing was loosening and manipulating around the A/C drier, but it is easily doable. 3 little screws hold it to the firewall, and there is only one electrical connector that is easily accessible on the blower.

Snarky
September 1st, 2010, 20:39
When I tried to remove the blower i could not clear the A/c accumulator. But it dose not hurt to try, like you said its only 3 bolts.

Jeff-97XJ
September 1st, 2010, 20:53
When I tried to remove the blower i could not clear the A/c accumulator. But it dose not hurt to try, like you said its only 3 bolts.

If you loosen the accumulator, the blower can be wiggled past it. The hoses that attach to the accumulator have some play in it, at least on my '97 it did. It has been around 4 months since doing this and my A/C still works great. No loss of freon.

Hope this helps-

SqueegieSteve
September 17th, 2010, 08:07
---- I went ahead and lumped the blower relay behind the glove compartment. For a while the blower motor worked great but now it has ceased to work again.

The fuse is still fine, what could be wrong now?

- For reference it seemed like the relay was functional but it was always switched. I figured it had something to do with the signal to the relay from the ignition (because when it is jumped i can turn the blower on even when the car is off)

bchulett
September 17th, 2010, 09:58
---- I went ahead and lumped the blower relay behind the glove compartment. For a while the blower motor worked great but now it has ceased to work again.

The fuse is still fine, what could be wrong now?

- For reference it seemed like the relay was functional but it was always switched. I figured it had something to do with the signal to the relay from the ignition (because when it is jumped i can turn the blower on even when the car is off)

Steve... check my recent threads regarding the HVAC controller, wires and connectors. I had this same problem and the tech claimed it started with a blower motor that was going south then affected the AC controller, melted a couple wire connectors on the AC controller, etc...

I chased this problem for a long time... 3 trips to the dealer, 1 fan switch, 2 controllers, 1 resistor, 1 blower motor, 1 trip to the wrecking yard, 2 controller wire connectors, etc.

.

SqueegieSteve
September 17th, 2010, 11:35
Steve... check my recent threads regarding the HVAC controller, wires and connectors. I had this same problem and the tech claimed it started with a blower motor that was going south then affected the AC controller, melted a couple wire connectors on the AC controller, etc...

I chased this problem for a long time... 3 trips to the dealer, 1 fan switch, 2 controllers, 1 resistor, 1 blower motor, 1 trip to the wrecking yard, 2 controller wire connectors, etc.

.

I read the thread.. are you meaning to say that it was just bad connections to your HVAC controller?

Ill check that out, but if that were the case then how come i still can't get it to work even after jumping that relay?

bchulett
September 17th, 2010, 12:18
I read the thread.. are you meaning to say that it was just bad connections to your HVAC controller?

Ill check that out, but if that were the case then how come i still can't get it to work even after jumping that relay?

Yes.... the plastic connectors at some point decided to melt at the connection on the controller during this whole ordeal.. at the fan blower switch and controller connector. They weren't like that when this all started, however it seemed like every time I changed a component the problem moved to the other end. This has been going on for several years... the dealer claims the blower motor started this. I can remember the motor speed would oscillate when the switch was on low.

I should have changed the blower motor at that point, but I didn't and the problem with the HVAC turning on and off randomly got worse as I started changing parts - the wrong ones first.

Fan switches are cheaper than the controllers.. once the controller gets hosed its $120 or more. Wire connectors are $3 each and need be located on a Jeep in a wrecking yard with the same controller.

Maybe your problem is different.. what relay?.. in the fuse box under the hood or the ones under the dash near the HVAC unit? On mine there are five relays driving the HVAC.. mine is a 1991.

.