Where is the Parking Aid Speaker located on a 2005 Ford Explorer?

It sounds like a communication issue to the BCM.

Code B1B50 Ford Left Rear Inner Parking Aid Sensor

AutoCodes https://www.autocodes.com > b1b50_ford
Aug 16, 2019 - The Parking Assist Control Module (PAM) monitors the Left Rear Inner Parking Aid Sensor. A continuous memory and on-demand Diagnostic Trouble ..

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https://www.youtube.com/watch?v=DtDgx7eM55c

Partstore knows

Parking Aid Navigator The parking aid system consists of the following:

• one radar sensor (located in the center of the rear bumper)
• two ultrasonic parking aid sensors (located on the left and right side of the rear bumper)
• parking aid module (located behind the LH C-pillar trim panel)
• parking aid speaker-audible warning tone (located in the parking aid module)

Expedition The parking aid system consists of the following:

• four ultrasonic parking aid sensors (located in the rear bumper)
• parking aid module (located behind the LH C-pillar trim panel)
• parking aid speaker-audible warning tone (located on the parking aid module)
• reverse gear select input (to the parking aid module from the reverse lamp circuit)
• The parking aid system is enabled when the ignition switch is in the RUN position and REVERSE is selected. The system can be disabled through the message center RESET switch located in the instrument cluster. The parking aid menu is displayed until the transmission is taken out of REVERSE. While the menu is displayed, pressing the message center RESET switch changes the parking aid system status to OFF.

First you need to read the code's to find out what the problem is , you don't just guess and replace part's . You really should take it to a qualified repair shop if you don't know that .
Parking Aid The parking aid system consists of the:

• parking aid sensors
• parking aid speaker
• parking aid module

The parking aid system is activated when the parking aid module receives a network messages from the instrument cluster indicating that the vehicle is in reverse. The parking aid system sounds a warning to alert the driver of stationary objects near the rear bumper when REVERSE is selected. The parking aid system assists the driver in detecting certain objects while the vehicle moves in reverse at speeds less than 4.8 km/h (3 mph). The parking aid system may not detect angular or moving objects.

Inspection and Verification

1. Verify the customer concern.

1. Visually inspect the following for obvious signs of electrical damage.
   
   Visual Inspection Chart Electrical
   • Smart junction box (SJB) fuse 18 (10A)
   • Circuitry
   • Connector(s)
   • Parking aid sensors
   • Parking aid speaker
   • Parking aid module

1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

1. If the cause is not visually evident, connect the diagnostic tool to the data link connector (DLC) and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
   • check that the program card is correctly installed.
   • check the connections to the vehicle.
   • check the switch position.

1. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.

1. Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
   • CAN circuit fault; all electronic control units no response/not equipped, refer to Section 418-00 .
   • No response/not equipped for parking aid module, Go To Pinpoint Test A .
   • System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out self-test diagnostics for the parking aid module.

1. If the DTCs retrieved are related to the concern, go to the Instrument Cluster Diagnostic Trouble Code (DTC) Index or the Parking Aid Module Diagnostic Trouble Code (DTC) Index.

1. If no DTCs related to the concern are retrieved, GO to Symptom Chart . Instrument Cluster Diagnostic Trouble Code (DTC) Index DTC Description Source Action U0159 Lost Communication With Parking Aid Module Instrument Cluster REPAIR all other DTCs first. If the DTC is still present Go To Pinpoint Test A . All Other DTCs - Instrument Cluster REFER to Section 413-01 .
   
   
   Parking Aid Module Diagnostic Trouble Code (DTC) Index DTC Description Source Action B1299 Power Supply Sensor Circuit Short to Ground Parking Aid Module Go To Pinpoint Test C . B1342 ECU is Faulted Parking Aid Module CLEAR the DTCs. REPEAT the parking aid module self-test. If DTC B1342 is retrieved again, INSTALL a new parking aid module. REFER to Parking Aid Module in this section. CLEAR all DTCs. REPEAT the self-test. B2477 Module Configuration Failure Parking Aid Module REFER to Section 418-01 . C1699 Left Rear Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1700 Left Rear Sensor Circuit Failure or Blockage Parking Aid Module Go To Pinpoint Test C . C1701 Left Rear Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1702 Right Rear Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1703 Right Rear Sensor Circuit Failure or Blockage Parking Aid Module Go To Pinpoint Test C . C1704 Right Rear Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1705 Left Rear Center Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1706 Left Rear Center Sensor Circuit Failure Parking Aid Module Go To Pinpoint Test D . C1707 Left Rear Center Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1708 Right Rear Center Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1709 Right Rear Center Sensor Circuit Failure Parking Aid Module Go To Pinpoint Test C . C1710 Right Rear Center Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1742 Rear Sounder Circuit Failure Parking Aid Module Go To Pinpoint Test F . C1743 Rear Sounder Circuit Short to Battery Parking Aid Module Go To Pinpoint Test F . U1900 CAN Malfunction - Missing Message Parking Aid Module REPAIR all other DTCs first. REPEAT the self-test. If DTC U1900 is still present, DIAGNOSE the system for a missing transmission range signal. REFER to Section 418-00 . U2051 One or More Calibration Files Missing/Corrupt Parking Aid Module REFLASH the parking aid module. If the DTC occurs after a software reflash, REFLASH the parking aid module again. If the DTC reappears after each attempt to reflash, INSTALL a new parking aid module. REFER to Parking Aid Module in this section. CLEAR all DTCs. REPEAT the self-test. Take your vehicle to a qualified repair shop before you cause more problems .

Try a good local junkyard, if they don't have it, most have a nationwide network, that will find it for you.

Dealer,Repair Shop or buy the factory diagnostic manuals,
as I do,so you can work on your own vehicles

Helm.Com ---for manuals

Check for a blowin fuse.

Have the RSS module checked for DTC'S - diagnostic trouble code's . That should always be the first step . An it is
Reverse sensing system Parking Aid The parking aid system consists of the:

• parking aid sensors
• parking aid speaker
• parking aid module

The parking aid system is activated when the parking aid module receives a network messages from the instrument cluster indicating that the vehicle is in reverse. The parking aid system sounds a warning to alert the driver of stationary objects near the rear bumper when REVERSE is selected. The parking aid system assists the driver in detecting certain objects while the vehicle moves in reverse at speeds less than 4.8 km/h (3 mph). The parking aid system may not detect angular or moving objects.

1. Visual Inspection Chart Electrical
   • Smart junction box (SJB) fuse 18 (10A)
   • Circuitry
   • Connector(s)
   • Parking aid sensors
   • Parking aid speaker
   • Parking aid module

Do you know what DTC'S are .

Parking Aid Module Diagnostic Trouble Code (DTC) Index DTC Description Source Action B1299 Power Supply Sensor Circuit Short to Ground Parking Aid Module Go To Pinpoint Test C . B1342 ECU is Faulted Parking Aid Module CLEAR the DTCs. REPEAT the parking aid module self-test. If DTC B1342 is retrieved again, INSTALL a new parking aid module. REFER to Parking Aid Module in this section. CLEAR all DTCs. REPEAT the self-test. B2477 Module Configuration Failure Parking Aid Module REFER to Section 418-01 . C1699 Left Rear Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1700 Left Rear Sensor Circuit Failure or Blockage Parking Aid Module Go To Pinpoint Test C . C1701 Left Rear Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1702 Right Rear Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1703 Right Rear Sensor Circuit Failure or Blockage Parking Aid Module Go To Pinpoint Test C . C1704 Right Rear Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1705 Left Rear Center Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1706 Left Rear Center Sensor Circuit Failure Parking Aid Module Go To Pinpoint Test D . C1707 Left Rear Center Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1708 Right Rear Center Sensor Circuit Short to Battery Parking Aid Module Go To Pinpoint Test D . C1709 Right Rear Center Sensor Circuit Failure Parking Aid Module Go To Pinpoint Test C . C1710 Right Rear Center Sensor Circuit Fault Parking Aid Module Go To Pinpoint Test E . C1742 Rear Sounder Circuit Failure Parking Aid Module Go To Pinpoint Test F . C1743 Rear Sounder Circuit Short to Battery Parking Aid Module Go To Pinpoint Test F . Your best bet , take it to a qualified repair shop . Ford

does the version come equiped with rear park sensors????????
Does your vehicle have or could have parking aid ? Yes . Free wiring diagrams here
http://www.bbbind.com/free-tsb Enter vehicle info year , make , model an engine size . Under system click on interior & driver Amenity ,then under subsystem click on parking Aid . Click the search button then the blue link. The parking aid module is located behind right rear trim panel
Parking Aid Module CAUTION: Electronic modules are sensitive to electrical charges. If exposed to these charges, damage may result.

1. Remove the RH interior trim. For additional information, refer to Section 501-01 .

1. Remove the parts in the order indicated in the following illustration and table.

Inspection and Verification

1. Verify the customer concern.

1. Visually inspect the following for obvious signs of electrical damage.
   
   Visual Inspection Chart Electrical
   • Central junction box (CJB) fuse 26 (7.5A)
   • Circuitry
   • Parking aid sensors
   • Parking aid disable switch and LED
   • Parking aid speaker
   • Reversing lamps

1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

1. If the cause is not visusally evident, connect the diagnostic tool to the data link connector and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
   • check that the program card is correctly installed.
   • check the connections to the vehicle.
   • check the ignition switch position.

1. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.

1. Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
   • SCP+, SCP-, UBP or ISP circuit fault; all electronic control units no response/not equipped, refer to Section 418-00 .
   • No response/not equipped for parking aid module, Go To Pinpoint Test BC .
   • System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out self-test diagnostics for the parking aid module.

1. If the DTCs retrieved are related to the concern, go to the Parking Aid Module Diagnostic Trouble Code (DTC) Index.

1. If no DTCs related to the concern are retrieved, GO to Symptom Chart to continue diagnostics