T-Roc AC Failure: Common Compressor Issue Explained

Had a similar issue with my 2017 T-Cross last summer. Having some experience with vehicle HVAC systems, I first suspected the AC compressor too, but it turned out to be the air conditioning control unit that was causing the complete system shutdown. The symptoms were identical, no cold air, system refusing to activate, and warning lights. After taking it to the workshop, their diagnostic revealed the control unit was not sending proper signals to engage the AC compressor. They replaced the control unit and performed a full air conditioning repair including an auto refrigerant recharge to ensure optimal performance. Total cost came to 980€. The repair process took about a day since they had to order the specific control unit. The car air conditioning has worked flawlessly since then. To better assist with your case, could you share: Have you noticed any unusual sounds when trying to activate the AC? Does the blower motor speed change when pressing the AC button? What specific error code is showing? Has there been any recent work done on the electrical system? These details would help determine if your issue matches what I experienced or points to a different component in the cooling system.

Had my T-Roc serviced just 3 weeks ago at 74945km and started noticing this issue right after. No unusual sounds when pressing the AC button, but definitely agree about checking the control unit first since the timing seems suspicious. The error code P0645 points to AC compressor circuit problems, which aligns with your experience regarding the control unit rather than a faulty compressor itself. Started gathering quotes for both scenarios, either control unit replacement or full AC compressor repair. The refrigerant leak test will likely be needed either way to ensure the system is properly sealed before any auto AC repair work begins. Did your repair include a warranty on both parts and labor? Would help me know what to expect when discussing options with the shop.

Thanks for those additional details about your T-Roc. The timing of the issue starting after service is definitely telling. With my T-Cross repair, I received a 2-year warranty on both the control unit and labor, which is pretty standard for major auto AC repair work. The P0645 code you mentioned matches exactly what my vehicle HVAC system was showing. This error typically indicates an electrical circuit issue rather than mechanical compressor failure. Since your car was just serviced, its worth checking if any connections to the cooling system components were accidentally disturbed during maintenance. Before accepting quotes, ask the shop to specifically check the wiring connections between the control unit and compressor. My repair could have been much more expensive if they had jumped straight to replacing the AC compressor without diagnosing the actual control circuit issue. The auto refrigerant recharge was included in my total repair cost, but make sure this is clearly specified in your quotes. A proper vehicle HVAC repair should always include pressure testing and refrigerant service to ensure the entire system functions correctly after any component replacement. Also confirm whether they plan to use OEM or aftermarket parts for the control unit if thats the route needed. The price difference can be substantial, though in my case the OEM unit has proven reliable.

Based on this helpful info, I feel much more confident about my upcoming repair. The circuit-related error code and the timing after service really point toward the control unit being the culprit rather than a full AC compressor failure. Going to request they thoroughly check all connections and wiring first, then proceed with control unit replacement if needed. Will definitely insist on OEM parts and make sure the warranty terms are clearly documented. Good to know a refrigerant leak test and recharge should be included in proper automotive cooling system repair. Going to schedule the work next week and make sure they fully diagnose before replacing any major components. Going to share the final repair details here once its resolved in case anyone else runs into similar air conditioning repair issues with their vehicle. Really appreciate all the specific information about what to watch for during the diagnosis and repair process.