HVAC System Malfunction Immediately After Sunroof Repair - Client2025
HVAC System Malfunction Immediately After Sunroof Repair by Mercedes-Benz of Spokane
Service Context and Immediate Change in Performance
On June 6, 2025, I brought my vehicle in for a sunroof repair due to a rattling noise for the second time. The vehicle remained in the dealership’s care for approximately 2.5 hours. Immediately upon picking it up while in their parking lot, I noticed a change in the A/C system's behavior.
Air from the vents became unusually and consistently cold, regardless of the temperature setting until the unit switched to heating.
The cabin climate became difficult to regulate — with uneven cooling, lower airflow, and imbalanced temperature distribution.
Functional Symptoms Post-Service
Over multiple long drives in ambient temperatures between 70°F–90°F, the following symptoms were observed:
• To achieve marginal comfort, now the temperature settings of either 79–81°F on auto are required or the vents must be completely turned away at the highest airflow setting — when previously the optimal comfort level was achieved at 66–71°F under similar conditions.
• The airflow remains uncomfortably cold, especially on the arms and face while other areas (back and legs) remain warm. The air from vents was either cold or warm, with little to no blending in between.
This unit behavior could not be considered within specifications. Even if a technically 'in-spec' system continuously outputs near-refrigerated air without regulating or properly blending airflow, it fails in terms of practical comfort and system design.
These symptoms indicate that the system is no longer responding dynamically to interior temperature needs. This behavior differs significantly from how the system performed prior to service.
This issue did not exist prior to the sunroof repair.
Dealership Conduct and Inadequate Follow-Through
• The issues were initially dismissed.
• Later a foreman acknowledged the abnormal behavior and said he would look for a solution.
Despite keeping the vehicle for a day and a half on July 2 and 3, and general manager Dan Crowley’s assurance that they had several ideas on what an issue might be after already consulting the technicians, who previously inspected the unit:
• Nothing was done to find a valid explanation for the issue.
• They unreasonably asked me to leave my car for a day and a half to only look for technical confirmation that would dismiss the existing issue.
• Notified me that insulation had been added to the roof area — a modification performed without my knowledge or consent, which could not reasonably have improved the issue based on the symptoms.
• Stated they had consulted PTSS, which only reflects that nothing might have been detected through their standard diagnostic procedures, not that the issue doesn’t exist.
• Returned the vehicle with the issue unresolved and entirely dismissed.
• Ignored detailed and credible reports of change in system behavior.
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