The BCM - body control module is what controls the power lock's , disconnecting power can cause some functions to need resetting .
Have the BCM checked for DTC'S - diagnostic trouble code's , that would be my first step . Do you know what wiring diagrams are an how to read them ? Free wiring diagrams here
http://www.bbbind.com/free-tsb Enter vehicle info. Year , make , model an engine size . Under system click on body & accessories , then under subsystem click on power lock's .
Battery Disconnect or Replacement Problems
Driver Door Unlock Operation
When any of the door lock switches are placed in the unlock position, a ground signal is applied to the BCM through the door unlock signal circuit. Upon receiveing this signal, the BCM grounds the control side of the driver door unlock relay through the driver door unlock relay control circuit. Since the other side of the driver door unlock relay winding is connected to battery voltage, the relay is energized. This causes the contacts to close and complete the path from the DRV LKS fuse through the battery voltage circuit. Voltage is then applied to the unlock side of the driver door lock actuator through the driver door lock actuator unlock control circuit. Since the other side of the the driver door lock actuator is connected to the normally closed contacts of the door lock relay to ground, the driver door unlocks.
The driver door unlock function can also be accomplished by the BCM supplying ground to the driver door unlock relay control circuit by either of the following:
• A keyless entry unlock transmission
• A lock out prevention function
DTC B3130 00: All Door Unlock Circuit
DTC B3135 00: All Door Lock Circuit
Circuit/System Description
When any of the door lock switches are placed in the lock position, a ground signal is applied to the BCM through the door lock signal circuit. Upon receiving this signal, the BCM grounds the control side of the door lock relay through the door lock relay control circuit. Since the other side of the door lock relay coil is connected to battery voltage, the relay is energized. This causes the contacts to close and complete the path from the battery voltage circuit. Voltage is then applied to the lock side of the door lock actuators through the door lock actuator lock circuits. Since the other side of the all the door lock actuators are connected to the normally closed contacts of their respective unlock relays to ground, the doors lock.
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