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Q: power locks won't work on 2003 mercury mountainner

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Just bought a used 2003 mercury mountainner and the power locks won't work, I have checked the fuses, or at least the right fuses. What can cause it to not work?

My car has 153876 miles.
My car has an automatic transmission.

Hello. Thank you for writing in. The first test needs to determine if the power locks work from any of their switches. If both front door panels and the key fob do not unlock the vehicle, then your issue is with the power supply. Issues like this are typically caused by a module issue or miscommunication. The switches utilize an actuator that is controlled by a solenoid. When you press the lock/unlock button, you are making the ground connection to the circuit and allowing the solenoid to energize the system. The fuses will then need to be checked first. If the fuses are ok, then you will want to look into the main control module for the power locks. This unit may have a bad connection, or may have failed altogether.

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