The vehicle in question, identified as the M100 Q edition with the chassis number LWLDMAMG1RL100222 and engine number 4KH1CN5MD HDK02686, was manufactured on December 6, 2023, with a mileage of only 20KM.
Upon receiving complaints of the air conditioning system's failure to cool and the subsequent malfunctioning of the compressor, Qingling Motors promptly initiated diagnostics. Given that the vehicles were exported overseas, the investigation initially focused on potential issues with refrigerant levels and the compressor relay. However, no anomalies were detected during the examination.
Further scrutiny revealed that the vehicle featured the Q-version interior AC design, prompting a verification process to ensure proper operation by the customer. Video confirmation confirmed that the AC switches were indeed applied correctly, ruling out misoperation as the cause.
Subsequent tests on the peripheral AC system also yielded no issues, leading engineers to review the circuit diagram of the automatic AC system. It was during this analysis that the decision was made to directly send signals to the AC compressor, resulting in the system functioning normally.
This series of tests and analyses led engineers to suspect a malfunction with the AC controller, especially considering reports of five other vehicles experiencing similar issues under identical circumstances.
Huanghai, an engineer from Qingling Motors, consulted with the factory and learned that the AC controllers may have been misinstalled. Specifically, it was revealed that there are two types of AC controllers for the 700mm wide chassis: 2X+D (Delphi) and 2X+B (Bosch). The six malfunctioning vehicles were intended to be fitted with the 700mm wide chassis Delphi system.
As a recommended course of action, customers were advised to remove and photograph the AC controller for confirmation. The absence of an 2X+D marking(2X) on the original vehicle further indicated the likelihood of a misinstallation.
In light of these findings, Qingling Motors has initiated corrective measures to rectify the misinstalled AC controllers, ensuring optimal performance and customer satisfaction moving forward.
Six AC controllers designed for 700mm wide chassis were dispatched to our international customers. Upon installation, the AC systems operated without issue.
However, an irregular startup pattern was observed with one of the AC compressors. Technicians abroad identified a malfunction in the AC evaporator temperature sensor. To address the issue, we promptly sent a replacement sensor overseas and facilitated its installation to restore proper functionality.
