Automatic running board not working how ti fix it?

If the automatic running board on your 2014-present GMC Sierra is not working properly, there are a few things you can check to try to diagnose and fix the issue.

1. Check for power: Make sure that the running board is getting power. Check the fuse for the running board and make sure it is not blown. If the fuse is good, use a voltmeter to test the power supply to the running board.
2. Check the motor: If the running board is getting power but not working, the motor may be the issue. Use a voltmeter to test the motor for power. If the motor is not getting power, check the wiring and connections to the motor.
3. Check the sensors: Many running boards have sensors that detect when the door is opened or closed. If the sensors are not working properly, the running board may not function correctly. Check the sensors for damage and make sure they are properly connected.
4. Check the control module: Many running boards have a control module that controls their operation. If the control module is not working properly, the running board may not function correctly. Check the control module for damage and make sure it is properly connected.
5. Check the running board itself: Finally, check the running board itself for damage or wear. If the running board is damaged or worn, it may not operate properly. Make sure that all of the mechanical components of the running board are in good working order.

If you are not comfortable working on your vehicle or are unable to diagnose and fix the issue yourself, it may be necessary to take your GMC Sierra to a qualified mechanic or dealership for repair.