I am suspecting a poor ground or other bad connection somewhere or possibily a defective door lock controller. [which is located next to the gas pedal] I would check the wiring there first. Remove both kick panels at front of doors, check grounds there. You would either need to ohm out all the wiring or gamble and get another controller.
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YesGO to A3 .
NoSERVICE the "GN/Y" wire.
YesREPLACE the electronic door lock control processor .
NoSERVICE the wire(s) in question.