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Old 11-25-2013, 03:56 PM
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Be an A/C Hero!

I'm having an intermittent issue with the air conditioner on my 2010 with the manual control. It "seems" like a blend door issue, but the gear for the blend door (which often breaks), just behind the glove box, is fine, and operates correctly.

My problem seems to be something behind the center console--that's where the noise is coming from. Here's what's going on:

MOSTLY: I get hot air on hot, and hot air on cold. If I turn the A/C on, it makes no difference. Hot air.

SOMETIMES: I try the A/C and it makes a "click" from behind the center console, and IT WORKS! But only if it makes this click. No click, no A/C, and hot air. Any ideas?
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Old 11-26-2013, 03:05 PM
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I'm an A/C Hero! (Kinda)

Okay, since everybody was so quick with the helpful suggestions (this my fourteenth unanswered thread on this topic), I decided to roll up my sleeves, disconnect the battery, and have a look under/inside the dash. Here are some discoveries:

1. The hot/cold blend door actuator is on the driver's side of the center console. Thanks to alldatadiy, I was able to identify the blend door (right there), the "air door" (just above it) and the recirc "mode door" (inside the glove box, mistakenly referred to online as the "blend door". If you have dual zone, you have another blend door on the right (pass) side of the center console. I don't.

2. Since I knew my problem was the hot/cold mix, I removed the blend door actuator. With it still connected, but laying away from the blend door, I started the car up and fiddled with the hot/cold. Oddly, the actuator rotated just fine.

3. I disconnected the battery, took a look at the blend door axle/gear that the actuator mates to, and tried twisting it. It twists PART of the way, but hangs up. Sure enough, it can twist fully to hot, but only part of the way to cold. If I jiggle it, and apply more twist, it will go all the way to cold.

4. With the blend door manually twisted all the way to cold, I started the car and threw the A/C on, and it blows bitter cold! Hooray!

5. Okay, so something is impinging the blend door from rotating fully. Clearly, the little actuator is not powerful enough to overcome this. So, what do I do to fix this? The blend door is buried in there, it seems, and it looks like major dash removal to get at this. Is there an easier way?

6. Barring any other ideas, I plan to stick a wooden dowel into the blend door gear, and figure out some way to twist the wooden dowel as I drive along. Sounds stupid, I know, but Option B is a two thousand dollar chase through the dash.

Help!
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Old 11-26-2013, 03:26 PM
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Re: Be an A/C Hero!

You should not have to remove the entire dash, but rather just the instrument panel silencer from the drivers side of the instrument panel:

SINGLE ZONE/DUAL ZONE DRIVER SIDE
1. Disconnect and isolate the negative battery cable.
2. Remove the instrument panel silencer from the
driver side of the instrument panel (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL SILENCER - REMOVAL).
3. Remove the three screws (1) that secure the blend
door actuator (2) to the driver side of the HVAC air
distribution housing (3).
4. Remove the blend door actuator from the air distribution
housing and disconnect the HVAC wire harness
connector (4) from the actuator.
5. Remove the blend door actuator from the vehicle.

Before getting into all that, have you tried recalibrating your blend door:

1. Turn the ignition to the ON position.
2. Turn the blower motor control to the OFF position.
3. Press and hold the EBL “rear window defrost” switch down and turn the blower motor control on. Continue to hold the EBL switch down until the EBL status indicator begins flashing, then release the mode switch. While the test / function is running the EBL status indicator will flash once per second. If the test / function passes, the EBL status indicator will stop flashing. If the test / function fail, the A/C and EBL status indicators will flash alternately.
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Old 11-26-2013, 03:35 PM
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Re: Be an A/C Hero!

Thank you, Dr, but I'm a couple steps ahead of this. I've gone in through the silencer, removed the actuator unit, determined it is GOOD, and I believe the BLEND DOOR (that the actuator twists open and closed) is not normally turning enough.

Either the door (inside the air box) or the axle is catching on something and not turning fully. When I twist it with my hand it will go part way and sieze. It takes a lot of force AND jiggling to get it all the way to cold.

That's why I don't think it's a calibration issue either. It's taking some serious torque (and jiggling) to move it fully. Thank you for your help, though.
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Old 11-26-2013, 04:42 PM
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Re: Be an A/C Hero!

Well, I put the old part back, and got it to work three times in a row--that's a new record. I'm hoping that the actuator normally puts out a lot of torque, and that it just needed a refresh/kick/calibration.

If I can't get it to work consistently I'll throw a new actuator in there and cross my fingers.

Since the problem first came up exactly a year ago (and then went away), and in a similar weather change, I think the problem is that the blend door (inside the air box) may have expanded enough to catch on something. The problem went away for a year, and now it's back. Like I said, I'll keep my fingers crossed. Thanks dr!
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Old 11-27-2013, 07:56 PM
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Re: Be an A/C Hero!

Blend door issues are pretty common on the WK's, usually manifesting as a loud clicking sound that lasts for a while until the door moves to the proper position. The problem seems to lie with the plastic gears, not the actuator itself. The little gears seems to wear down and skip, causing the loud clicking. There was a company that made a fix, it involved cutting open the hvac assembly (not a major as it sounds) to gain access to the gearset and replacing it with metal. I don't remember the name but a full internet search should dig it up.
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Old 12-02-2013, 11:40 AM
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Re: Be an A/C Hero!

Yeah, after much googling I can see that it's a long-term DIY thing. The cost to RnR the dash is so much, and subject to so much potential x-factor, I just can't see myself ever taking it in to the dealer. Before that, I would probably cut into the dash and replace the whole airbox myself, and just live with a cut-up dash.

Current status is that the blend door works more often than it did recently, although it was 100% good for the prior twelve months. I think that door is sticking as it moves (not the axle but the door vane). Maybe there is loose rubber facing on it?

Thanks again for the comments, and I'm grateful for any further ideas!
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Old 12-03-2013, 10:29 AM
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Quote:
Originally Posted by dr.lee.baugh View Post
Before getting into all that, have you tried recalibrating your blend door: 1. Turn the ignition to the ON position. 2. Turn the blower motor control to the OFF position. 3. Press and hold the EBL “rear window defrost” switch down and turn the blower motor control on. Continue to hold the EBL switch down until the EBL status indicator begins flashing, then release the mode switch. While the test / function is running the EBL status indicator will flash once per second. If the test / function passes, the EBL status indicator will stop flashing. If the test / function fail, the A/C and EBL status indicators will flash alternately.
How long should this test take? I tried running it this morning before getting out of my car and going into work. I heard the test taking place for a minute or two, then didn't hear anything but my EBL light was still flashing. At no point was the AC light flashing so I'm not sure what that means? I had to go so I just turned off my car and left. Any help?
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Old 12-03-2013, 01:36 PM
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Re: Be an A/C Hero!

I'm not sure how long it should take to test the actuators and re-calibrate, since I have the ATC system (which is calibrated over the CANBUS).

If you just want to check for HVAC DTCs, you can perform the following:

1. Turn the ignition to the On position.
2. Turn the blower motor control to the On position.
3. Press the A/C mode switch down, turn the
blower motor control to the Off position, wait 5 seconds
and then release the A/C switch. If there are
active or stored DTCs to display, the A/C status
indicator will begin to flash. If there are no
active or stored DTCs to display, the LEDs on the
A/C-heater control will turn off and the system
will automatically exit the mode of operation.
4. To manually exit Display DTC Mode, either turn the ignition off or disconnect the negative battery cable from the
battery.
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Old 12-29-2013, 03:31 PM
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Re: Be an A/C Hero!

My girlfriend's son who is a dealership Jeep mech (names changed to protect the innocent and hardworking), said that this is a bad heater box problem - says it's a common problem. Says that the actual problem is that there is a plastic tab (that was supposed to be removed during manufacture) on the box, that the blend door hangs up on when moved by the actuator. When the actuator is new, it apparently has enough torque to overcome the tab. But as it ages, it doesn't have enough strength to move door past the tab. The only real fix is to RnR the dash and replace the box (approx $300). He says that short of the RnR dash and box replace, you're doing the best temp workaround that exists by manually moving the door past the tab.

Lastly - he said that since yours is not that old (2010?), that if you call Chrysler and beef loudly about this manufacturing defect (and it being a common problem) that you may be able to get them to pay for it. Hope this helps. Bob W, Bristol RI, US (05 WK).
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Old 12-30-2013, 11:23 AM
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Re: Be an A/C Hero!

Thank you, Bob, that's exactly what I'm seeing. Now that I've RnR the SAME actuator, it works "better". I'm thinking come spring I will RnR a NEW actuator and see if it helps.

Regarding the Chrysler chain of complaint, a couple issues stare at me:

First, to get this moving, I have to take it into the dealer and have them "diagnose" the problem. Since it is not a warranty item (currently), I will have to pay to let them fool around and discover what I already know. Only then can I push Chrysler for "assistance", with no assurance I'll get ANY money. I called them a few weeks back and that is what I was told.

Secondly, to replace the airbox the dash must be pulled. This is a big job that must be done with care at every step. Do I trust this to the dealer that winched my spare tire on upside down?

So right now I'm reluctant to pull the dash. I'd love to get a look at a schematic for the heater box and see exactly where that offending tab is sitting. Maybe there is some way I can go at it with a drill/heat gun/jab saw/ABS cement/chewing gum. I've seen reports online where people simply cut the dash strut that sits in front of the box and pulled it, then splinted a new piece onto the strut. I feel better about doing that than letting it sit at the dealer for a week running up a blind tab.

Thanks for your help!
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