This is from the Ford Workshop DVD....Parking Aid Module (PAM)
Might work and not give any DTC's if you disconnect the speaker.
Removal and Installation
If replacing the PAM only, proceed as follows:
Disconnect the electrical connectors.
Remove the 2 pin-type retainers and the PAM .
If replacing the parking aid speaker only, proceed as follows:
Disconnect the parking aid speaker electrical connector.
Disengage the parking aid speaker clips.
Remove the parking aid speaker.
To install, reverse the removal procedure.
PAM is located behind the left hand side of Instrument Panel.