Pinpoint Test F: Loud Popping Sound From The Audio Speaker(S)

WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

F1 CHECK CIRCUIT 1003 (GY/YE) FOR OPEN OR SHORT TO GROUND
- Key in ON position.
- Key in START position.
- Measure the voltage between the audio unit C240b-3 (DM100 and Single CD) or C290a-15 (CD6), circuit 1003 (GY/YE), harness side and ground: with the key in RUN and START positions.
  
  Fig 1: Checking Circuit 1003 (GY/YE) For Open Or Short To Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage 0 volts with the key in RUN and greater than 10 volts with the key in START position?
Yes

GO to F2.

No

REPAIR the circuit. TEST the system for normal operation.
F2 CHECK SUBWOOFER ENABLE LINE - CIRCUIT 168 (RD/BK) FOR SHORT TO BATTERY POWER
- Disconnect: Subwoofer Amplifier C466.
- Key in START position.
- Measure the voltage between the subwoofer amplifier C466-1, circuit 168 (RD/BK), harness side and ground.
  
  Fig 2: Checking Subwoofer Enable Line - Circuit 168 (RD/BK) For Short To Battery Power
  Courtesy of FORD MOTOR CO.
- Is voltage present?
Yes

REPAIR the circuit. TEST the system for normal operation.

No

GO to F3.
F3 CHECK AUDIO UNIT
- Leave subwoofer amplifier C466 disconnected.
- Is the popping sound still present?
Yes

REMOVE the audio unit and SEND it to an authorized audio system repair facility. TEST the system for normal operation.

No

Remove the subwoofer amplifier and SEND it to an authorized audio system repair facility. TEST the system for normal operation.