If you have a factory set up. Even if you hit the button by accident. It won’t engage it! That’s why people do the grey wire mod. To engage WHENEVER they desire. The computer won’t engage the locker at high speeds or if it’s not in 4lo.

Op can easily jack up the rear and have someone hit the button and listen if the motor even works at all. If it does, it should easily lock especially when of the ground. If not, take the motor apart. The elocker motor MUST BE PROPERLY CLOCKED in order to work properly. If someone has taken the motor out before out of the housing. You must connect power to it. LOCK IT , lock the rear manually. Install the locker. Then unlock it. That’s how you properly clock and install the elocker motor.