16 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHHelp needed w/ Climate Control Module
Leading reported evidence
Use ones
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I think the modules are pricey, but there are always used ones on eBay.
Leading evidence: 'Use ones' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Adjust fan speed up or down' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Then use the blower speed to adjust the system outflow cooling to your comfort zone.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Try pulling the module out, removing the connector, and cleaning the contacts.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I just thought that because some many of the controllers had bad displays, somebody might have a spare controller with a bad display they replaced instead of repaired that he could use for troubleshooting.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Changing the setpoint to maximum cooling results in bypassing the reheat/remix aspect of the system and thereby a much lighter load on the A/C compressor.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
16 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T031046Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
'02 C4 cab w/ 57k mi on the clock - today the CCM stopped functioning properly. Compressor comes on, A/C is working but won't blow thru vents.
Getting erratic behavior as follows: Defroster is activated which is blowing cold air to the windshield. When I attempt to deactivate the defroster, each time I hit the button the fan speed drops down a notch. When I try depressing the Auto button, Temp up or down, or Fan speed up or down, nothing happens. Sometimes when I hit the Defroster button the Recirculating icon comes on - but the Recirc button won't turn it off...
I tried turning the car on/off several times and the erratic behavior continues. It completely shut down one time and would not activate until cycling power to the car again.
No CEL or other warning lights coming on. Any idea what's going on? I'd sure appreciate some help as the summer heat has returned to Colorado. Thanks in advance!
Update - after sitting for 3 hours during meetings, upon startup the system started working as normal and performed well during the 1-hr drive home. All appears to be well and hopefully no future recurrence.
Not sure of your statement, question(?) overall, but....
Make sure the front radiator fans are both capable of running FULL TILT if and when needed. The system will AUTOMATICALLY switch off A/C functionality if the engine ECU detects (computes?) that the engine coolant level is rising (to)rapidly and might soon reach overheating.
This is considered normal operation for a car that is expected to be driven so hard at times that the additional A/C condenser heating load to the engine coolant radiators must be sacificed. No error codes result.
If you see it happen again the you can increase the cooling efficiency of the A/C quite dramatically via using the maximum cooling mode of the system. Changing the setpoint to maximum cooling results in bypassing the reheat/remix aspect of the system and thereby a much lighter load on the A/C compressor.
Then use the blower speed to adjust the system outflow cooling to your comfort zone.
Gremlins! Yesterday for the first time my up/down temperature selector worked in opposite function and my PSE light was on-5 minutes into drive all normal. WTF
My climate control problems persist and none of the typical adjustments work:
Can't go into AUTO mode
Can't turn off compressor
Can't adjust temp up or down
Can't adjust fan speed up or down
It's either all "OFF" in manuell mode, or the system is all "ON" w/ compressor, defroster, full fans and temp locked at 72 deg. The only way to switch is by pressing the recirculation switch - all other switches are inoperable.
I hooked up a code reader, but no codes are present.
Could it be true that I have a bad ignition switch as mentioned by b8_rdc? I'd gladly pay the $9 to fix this issue before the snow flies...thanks for any help w/ this annoyance.
I've replaced the headlight switch and managed that task - is the ignition switch a more challenging project? I don't tend to wrench on my own cars, but I've been able to do a fair amount on the Pcar thus far.
Try pulling the module out, removing the connector, and cleaning the contacts. Reassemble with dielectric grease. I've cured some weird behavior in both the climate control and the instrument cluster after doing this.
Thanks, 86Meesta2 - after reviewing the ignition switch procedure I'm not sure how this will fix the CCM, but your advice seems to make more sense. I find it hard to believe I'm the only 996 owner to ever encounter this problem.
From the variety of symptoms and flakiness of behavior, it does sound like it's the climate control computer itself.
Removing/refitting the connectors and using some electronic contact cleaner and/or dielectric grease can't hurt, though use the grease very sparingly. It might be short lived fix even if it helps... More likely you have a failing component inside the module or a bad trace somewhere, and heating/cooling and current cycles cause it to behave erratically.
I think the modules are pricey, but there are always used ones on eBay.
The displays on those modules fail frequently, they still work but segments go bad on the display. Maybe somebody has a working module with a damaged display that you could borrow to swap in for troubleshooting?
Also, not sure how much help it will be, but here's the schematic for the HVAC control systems... (click for full res)
A bit off-topic, but there are several types of display repair kits for these climate control displays. One even is a perfect match for the OEM display.
Doesn't sound like that's the OP's problem, though.
Right... I just thought that because some many of the controllers had bad displays, somebody might have a spare controller with a bad display they replaced instead of repaired that he could use for troubleshooting.
This is a source reference. Confirm exact model applicability in the original material.
