Q: Car doors lock but won't unlock with interior button?

asked by on August 03, 2017

I have a 2004 Hyundai Sonota. When I hit the lock button all four of my doors lock but when I hit unlock nothing happens except a slight noise that sounds like the motors tried but didn t have enough power. I m hoping just replacing the drivers side actuator will fix the problem but i don t want to spend the money if that isn t the problem. Any advice would be extremely helpful, thank you.

Hello, thank you for writing in. Before replacing the switch or actuator, you want to take the switch out and make sure it is not dirty or has a damaged connection. Chances are, the switch is simply not allowing enough voltage through to actually unlock the doors. Again, check the unlock button for a poor wiring connection, a dirty switch, or any other sort of obvious damage. If nothing seems to be wrong, it is a good time to do electrical testing while you have access. Use a voltmeter to measure the voltage and the voltage drop when you press the button. If the switch has power, but is not passing the power to the locks at each door, the switch needs to be replaced. For more help with testing, contact our service department to schedule an appointment.

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