Pinpoint Test J: DTC B2633 Driver - Front Microphone Circuit Failure

WARNING: This page is about a different car, the 2005 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

J1 CHECK THE VOICE SIGNAL INPUT
- Key in OFF position.
- Disconnect: Navigation System Module C4209.
- Key in ON position.
- Measure the voltage between the navigation system module C4209 pin 7, circuit 1196 (DG/WH), harness side and between the navigation system module C4209 pin 19, circuit 1197 (LG/BK), harness side while speaking loudly into the interior rear view mirror microphone.
  
  Fig 1: Measuring Voltage Between Navigation System Module C4209 Pin 7, Circuit 1196 (DG/WH), Harness Side And Between Navigation System Module C4209 Pin 19, Circuit 1197 (LG/BK), Harness Side
  Courtesy of FORD MOTOR CO.
- Is any AC voltage indicated?
- Yes : GO to J6.
- No : GO to J2.
J2 CHECK CIRCUIT 964 (DB/LG) FOR VOLTAGE
- Key in OFF position.
- Disconnect: Interior Rear View Mirror C9012.
- Key in ON position.
- Measure the voltage between the interior rear view mirror C9012 pin 13, circuit 964 (DB/LG), harness side and ground.
  
  Fig 2: Measuring Voltage Between Interior Rear View Mirror C9012 Pin 13, Circuit 964 (DB/LG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to J3.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
J3 CHECK CIRCUIT 676 (PK/OG) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the interior rear view mirror C9012 pin 2, circuit 676 (PK/OG), harness side and ground.
  
  Fig 3: Measuring Resistance Between Interior Rear View Mirror C9012 Pin 2, Circuit 676 (PK/OG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to J4.
- No : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.

J4 CHECK CIRCUITS 1196 (DG/WH) AND 1197 (LG/BK) FOR AN OPEN AND A SHORT TO GROUND

Measure the resistances between the navigation system module C4209 pins harness side and the rear view mirror C9012 pins harness side; and between the navigation system module C4209 pins harness side and ground as follows:

INTERIOR REAR VIEW MIRROR PIN SPECIFICATION

Navigation System Module Pin	Interior Rear View Mirror Pin	Circuit
C4209 pin 7	C9012 pin 9	1196 (DG/WH)
C4209 pin 19	C9012 pin 10	1197 (LG/BK)

Fig 4: Measuring Resistances Between Navigation System Module C4209 Pins Harness Side And Rear View Mirror C9012 Pins Harness Side; And Between Navigation System Module C4209 Pins Harness Side And Ground

Courtesy of FORD MOTOR CO.

Are the resistances less than 5 ohms between the navigation system module and the interior rear view mirror, and greater than 10,000 ohms between the navigation system module and ground?

Yes : GO to J5.
No : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.

J5 CHECK CIRCUITS 1196 (DG/WH) AND 1197 (LG/BK) FOR A SHORT TO VOLTAGE
- Key in ON position.
- Measure the voltage between the navigation system module C4209 pin 7, circuit 1196 (DG/WH), harness side and ground; and between the navigation system module C4209 pin 19, circuit 1197 (LG/BK), harness side and ground.
  
  Fig 5: Measuring Voltage Between Navigation System Module C4209 Pin 7, Circuit 1196 (DG/WH), Harness Side And Ground; And Between Navigation System Module C4209 Pin 19, Circuit 1197 (LG/BK), Harness Side And Ground.
  Courtesy of FORD MOTOR CO.
- Is any voltage indicated?
- Yes : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
- No : INSTALL a new interior rear view mirror. REFER to REAR VIEW MIRRORS . CLEAR the DTCs. REPEAT the self-test.
J6 CHECK FOR CORRECT NAVIGATION SYSTEM MODULE OPERATION
- Disconnect all the navigation system module connectors.
- Check for:
  - corrosion
  - pushed-out pins
- Connect all the navigation system module connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new navigation system module. REFER to NAVIGATION SYSTEM MODULE . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.