2009 Mercury Mariner Hybrid Problems

RepairPal has identified the most common problems with the 2009 Mercury Mariner Hybrid as reported by actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.

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Known Problems

The hybrid models have a coolant pump that cools control electronics. The pump can fail or spin slowly, which causes a Check Engine Light to illuminate and complete engine shut down.

The Check Engine Light may illuminate with code P0442, P0456, and/or P1450. These codes are related to the EVAP system. Our technicians tell us that if no EVAP system faults are confirmed, updated software is available for the powertrain control module (PCM) which should correct this concern.

Hard driving conditions, including quick starts from a stop and hard acceleration up hills, can cause the rear motor mount to crack. The broken motor mount needs to be replaced, otherwise damage to the hybrid drive system may result.