PT Cruiser's Climate Control & Dash Warnings Nightmare

Had similar issues on a Chrysler 300C Diesel from 2010. The dashboard warning lights and climate control problems pointed to a corroded wiring harness connector near the HVAC control module. The automotive sensor cluster was fine, but moisture had damaged the main connector plug. The washer nozzle freeze-up and mirror heating failure were also linked to this wiring issue. What seemed like multiple problems was actually one failing connection point. The repair involved removing the lower dash panel, cleaning the connector pins, and applying dielectric grease to prevent future corrosion. While not a major mechanical issue, accessing the area was labor-intensive since several components needed removal first. The symptoms match yours exactly, unusual dashboard warnings, climate control malfunction, and auxiliary systems failing. Worth checking the wiring before replacing the humidity sensor. The connector deterioration is a known weak point on these models and often misdiagnosed as sensor failure. This repair needs proper diagnostic equipment to verify the issue. A basic code reader might not show the intermittent connection problems that cause these symptoms.

Thanks for sharing your experience with the 300C. I had these exact issues with my 2007 PTCruiser last winter. The electrical issue started with unusual warning lights, then the visibility got worse as the windshield fogging became uncontrollable. After reading your post, I checked with a different mechanic who confirmed the wiring harness malfunction near the HVAC module. Sensor calibration wasnt the problem after all, just that corroded connector you mentioned. Really helped avoid an unnecessary sensor replacement. Did the repair hold up well for you? What was the final cost for the fix? Wondering if any other electrical problems showed up later.

The repair has been solid since getting it fixed, no more car sensor issues or unusual warnings on the dashboard. The windshield fogging problem completely disappeared after they repaired the corroded connector. Total cost was 95€, which mainly covered labor since accessing the wiring harness is time-consuming. The humidity sensor and climate control have worked perfectly since the repair. No additional electrical problems have surfaced in the months following. The visibility is consistently clear now that the system properly manages cabin humidity levels. This fix was much more cost-effective than replacing components unnecessarily. The malfunction really was just that connector issue, exactly as suspected. Having the right mechanic who understood these common wiring problems made all the difference. The investment was worth it for reliable climate control operation and clear visibility in all weather conditions. These connector issues can be tricky to diagnose, but once properly fixed, they typically stay resolved.

After dealing with those frustrating dashboard warnings and climate control problems, I finally got my PTCruiser properly diagnosed and fixed. The second mechanic I visited really knew what they were doing, opened up the lower dash, found that corroded connector, and cleaned it all up within a few hours. The repair cost me 120€ total, which feels like a bargain considering I was worried about needing a new humidity sensor and complete HVAC overhaul. The automotive sensor readings are all normal now, and the visibility has improved dramatically with proper climate control function. All those warning lights are gone, the AC runs perfectly, and even the washer nozzles work great in cold weather. Really glad I got a second opinion instead of jumping into expensive parts replacement. The mirror heating started working again too, which is a nice bonus. What seemed like multiple system failures turned out to be one simple wiring issue. Should have known there was more to it when the sensor calibration came back normal but problems persisted. Lesson learned, find a mechanic who actually traces the problem rather than just reading error codes.