2010 Mercury Mountaineer Problems
RepairPal has identified the most common problems with the 2010 Mercury Mountaineer based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
A failed heater blend door or actuator can cause the temperature control for the HVAC system to stop working. A clicking sound from the dash area would commonly indicate an actuator fault. If the heater gets stuck on the hottest setting, the heater blend door may be broken requiring replacement of the heater box to repair the issue.