Dead HVAC Panel, Blower Motor & Control System Guide

Had the exact same issue on my 2019 Chevy Malibu last winter. Turned out the temperature sensor and power supply to the climate control module were both failing. The symptoms match yours perfectly, dead panel and minimal HVAC function. The root cause was a damaged wiring harness connector behind the control panel, which caused intermittent power issues. This affected both the blower motor operation and the entire climate control system. The fix required: Testing the power supply circuit, Replacing corroded connector pins, Installing a new temperature sensor, Recalibrating the HVAC module It wasn't a quick fix but wasn't super serious either. Make sure your mechanic: 1. Checks all connector pins for corrosion 2. Tests the temperature sensor readings 3. Verifies power supply voltage at the module 4. Runs a full system diagnostic scan Don't let them just replace the control panel without checking these other components first, could be wasting money on parts you don't need.

Thanks for the detailed breakdown, this really helps narrow down what could be wrong with my HVAC system. The symptoms with the control panel and air conditioning sound identical to what you experienced. Did you remember roughly what the total repair cost came to? Also curious if you've had any electronic faults pop up since they fixed the wiring harness and replaced those components? My biggest concern is spending money on repairs only to have issues return later. Sounds like I'll definitely need a thorough diagnostic scan to identify if it's just the control panel or if there are other underlying problems with the power supply and sensors.

Just wanted to update on the repair cost since getting my HVAC system fixed, it came to 95€ total, which was mainly for fixing a faulty electrical connector in the wiring harness. Way less than I initially feared! The mechanic found the root cause pretty quickly, just a bad connection that was interrupting the power supply to the climate control panel. Once they repaired that connection, everything started working perfectly again. No more dead display or HVAC problems. Best part is I haven't had any electronic faults or issues since the repair. The climate control has been working flawlessly for months now. No temperature sensor problems, no connectivity issues, everything's stayed stable. You're definitely on the right track getting a full diagnostic scan. In my case, what seemed like it might need expensive component replacements turned out to be just a simple wiring fix. Having a thorough mechanic who checks all the electrical connectors before replacing parts saved me a bunch of money.

Took my car to the shop yesterday after getting that helpful advice. Similar to what others mentioned, the mechanic found issues with the wiring harness connected to the climate control module. The air conditioning system wasn't getting proper power because of some corroded pins in the connector. The diagnostic scan showed the power supply was intermittent, which explained why the control panel would sometimes work and sometimes be completely dead. They cleaned up the connections, replaced a few damaged pins, and tested all the sensor readings. Total bill came to less than expected, mostly labor for electrical diagnosis and fixing the connections. Much better than replacing the entire control panel like I initially feared. Just drove it home and everything's working perfectly, got cold air blowing and all the panel buttons responding again. Definitely glad I asked here first and knew what to have them check. Having them focus on the wiring and power supply issues rather than just swapping parts saved me some serious cash. The whole repair took about 3 hours start to finish.