gas tank door is locked on mercedes C230
The fuel door is controlled by a vacuum motor which runs off a vacuum pump which is behind the right rare panel in the trunk. the vacuum hose to the fuel tank door motor might have a leak or is disconnected or the vacuum motor has failed. As well as the vacuum pump could be faulty. Does your central locking system still works on the car doors? if so, then the problem is isolated to just the fuel tank door vacuum motor.
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