Auto door lock

I replaced the rear drivers side automatic lock unit in my 2001 escape and can only use it manually! I have power to the unit and at first I thought it must be defective so I returned it and got a second NEW unit. Same problem! If I take the original unit and connect it to the power it makes noise as if it's working. The reason I replaced it was because the locking bar would not engauge.

A friend thinks that the unit has to be programmed by ford...I cannot believe this at all.

Any suggestions!