The power door lock circuit has no relay.
Just the two door switches and the two door lock motors.
Power is from a 30amp PWR ACCY Circuit Breaker located in the fuse panel.
The right door lock is controled by the Theft Deterrent Control Module. The TDCM is located Behind the RH side of I/P near fuse block.
It stops when I pull the 30A breaker which is how I isolated the circuit.
Do the door locks operate properly?
Can you set the alarm and also disarm it?
That Breaker also provides 12 volts to the power seats.
Disconnect the power seat connectors under the seat cushions and see if that solves the buzzing problem. Could the sound you hear be coming from the 30 amp breaker?