2000 Jeep Grand Cherokee Air Conditioning Problem

[2000XJ]

My girlfriend's mom's 2000 Grand Cherokee Limited is having an AC issue...

The AC system is the one with the separate temperatures settings for the driver and passenger sides.

One moment the AC will be running just fine, and then it just stops blowing air, but electronically everything is on and lit up.

Any ideas/suggestions?

[Doobie]

it could be the refrigerant wearing out. Its the most common problem with AC

[2000XJ]

No, I mean it literally stops blowing air. The airflow from the vents stops. The only way to get it to blow again is to shut it off and restart, and then it happens all over again.

[Doobie]

thats odd. maybe its the climate control...

[garett73]

yea i heard the ac goes out all the time on the dual climate control models i'll ask my buddy if he figured out how to fix his and let you know

[Doobie]

Just be careful with who does the work. my cousin had a 03 GC with the climate control and they took out his whole dash and then fixed it, but then the dash squeaked and rattled.

[WJCraig]

Check you're wiring harness that goes into the blower motor resistor block/blower motor controller. The harness is known to get hot and melt to the block/controller. Normally causes intermittent operation, then eventually no air at all...









If this is your problem, the harness repair kit is Mopar Part Number: 05102406AA.




Later.

[WJCraig]

Oh, it's under the dash on the passenger side...You can see it hanging down without taking anything apart.

You can also check for ac fault codes using the following procedure:

To enter the self-diagnostic mode:

1. Depress the a/c and recirc buttons at the same time and hold. Rotate the left temperature control knob clockwise (CW) one detent.

2. If you continue to keep the a/c and recirc buttons depressed, the AZC control module will perform a Segment Test of the Vacuum Fluorescent (VF) display. In the Segment Test you should see all of the display segments illuminate as long as both buttons are held. If a display segment fails to illuminate, the vacuum fluorescent display is faulty and the a/c heater control must be replaced.

3. After viewing the Segment Test, release the A/C and Recirc buttons and the display will clear momentarily. If a 0 is displayed, then no faults are set in the system. Should there be any faults, either current or historical, all fault codes will be displayed in ascending numerical sequence (note no effort is made to display fault codes in chronological order). Each fault code is displayed for one second before the next code is displayed. Once all fault codes have been displayed, the system will then repeat the fault code numbers. This will continue until the left side set temperature control is moved at least one detent position in the CW direction or the ignition is turned OFF.

[WJCraig]

Here's a list of fault codes:

Current Faults

Input Faults:
01 = IR thermister circuit open
02 = IR thermister circuit shorted
03 = Fan pot shorted
04 = Fan pot open
05 = Mode pot shorted
06 = Mode pot open
07 = IR sensor delta too large
08 = Reserved
09 = Reserved
10 = One of four motor drivers has drive 9A9 shorted to ground
11 = Engine air intake temperature Buss message missing
12 = Country code Buss message missing

System Faults:
13 = Mode motor not responding
14 = AI (Recirc) motor not responding
15 = Left temperature door not responding
16 = Right temperature door not responding
17 = Mode door travel range too small
18 = Mode door travel range too large
19 = AI (Recirc) door travel too small
20 = AI (Recirc) door travel too large
21 = Left temperature door travel too small
22 = Left temperature door travel too large
23 = Right temperature door travel too small
24 = Right temperature door travel too large
25 = Calibration check sum error
26 = Engine coolant temp bus message missing
27 = Vehicle speed bus message missing
28 = Engine RPM bus message missing
29 = OAT bus message missing
30 = Display intensity bus message missing
31 = VIN number bus message missing
32 = Raw OAT bus message missing


Historical Faults

Input Faults:
33 = IR thermister circuit was open
34 = IR thermister circuit was shorted
35 = Fan pot was shorted
36 = Fan pot was open
37 = Mode pot was shorted
38 = Mode pot was open
39 = IR sensor delta was too large
40 = Reserved
41 = Reserved
42 = One of four motor drivers had drive 9A9 shorted to ground
43 = Engine air intake temperature Buss message missing
44 = Country code Buss message missing

System Faults:
45 = Mode motor was not responding
46 = AI (Recirc) motor was not responding
47 = Left temperature door was not responding
48 = Right temperature door was not responding
49 = Mode door travel range too small
50 = Mode door travel range too large
51 = AI (Recirc) door travel range too small
52 = AI (Recirc) door travel range too large
53 = Left temperature door travel too small
54 = Left temperature door travel too large
55 = Right temperature door travel too small
56 = Right temperature door travel too large
57 = Calibration check sum error
58 = Engine coolant temp bus message missing
59 = Vehicle speed bus message missing
60 = Engine RPM bus message missing
61 = OAT bus message missing
62 = Display intensity bus message missing
63 = VIN number bus message missing
64 = Raw OAT bus message was missing

[Doobie]

I think that Craig has answered you question much better than I have..... to you Craig!

[WJCraig]

I do what I can...The harness was an issue I just sorted out, so I just happened to have the info fresh in my mind...

Hope the info helps you out, 2KXJ...

[2000XJ]

Craig thanks alot! I'm putting my money on the fact that the relay/module that you pictured before is what went bad. Hopefully this will be fixed sooner than later. Thanks a bunch!

[Doobie]

Lets us know how it turns out. I am curious about it.

[scooter6109]

I saw some good posts on this site and was hoping someone could venture a guess about what might be happening on my car. The AC system either works or doesn't, but when it doesn't the dashboard control completely blanks out (like no power is getting to it). Sometimes it comes back, sometimes it doesn't but it is an intermittent problem as opposed to an outright failure. The problem initially started after a radiator replacement. I notice there are two wiring harnesses near the radiator and I'm thinking they're somehow related to my AC problem, like maybe they just yanked the connectors apart instead of disconnecting them normally. Does anybody have a suggestion for why the display goes away, or know what those two wiring bundles are controlling? One of the bundles appears to go to the AC compressor so I know it's at least partially related to my problem!
Thanks, Tom

[WJCraig]

Most likely a short in the wiring somewhere...but at to where exactly? I'd start by tracing backwards from the control panel first, and see what you can find.