Pinpoint Test K: DTC B2633 Driver - Front Microphone Circuit Failure: Overview

Test Step 

1. K1 CHECK VOICE SIGNAL FROM THE MICROPHONE 
   • Key in OFF position.
   • Disconnect: Navigation System Module C4209.
   • Key in ON position.
   • Measure the voltage between the navigation system module C4209-7, circuit 8-MC8 (WH/RD), harness side and between the navigation system module C4209-19, 9-MC8 (BN/RD), harness side while speaking loudly into the rear view mirror microphone.
     Fig 1: Checking Voice Signal From Microphone

     Courtesy of FORD MOTOR CO.
   • Is any AC voltage indicated? 

   Result / Action to Take 

   1. Yes  : GO to  K6.
   2. No  : GO to K2.
2. K2 CHECK CIRCUIT 75-AD15 (YE/BU) FOR VOLTAGE 
   • Key in OFF position.
   • Disconnect: Rear View Mirror C911.
   • Key in ON position.
   • Measure the voltage between the rear view mirror C911-13, circuit 75-AD15 (YE/BU), harness side and ground.
     Fig 2: Checking Circuit 75-AD15 (YE/BU) For Voltage

     Courtesy of FORD MOTOR CO.
   • Is the voltage greater than 10 volts? 
   1. Yes  : GO to K3.
   2. No  : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
3. K3 CHECK CIRCUIT 31-AD15 (BK) FOR AN OPEN 
   • Key in OFF position.
   • Measure the resistance between the rear view mirror C911-2, circuit 31-AD15 (BK/OG), harness side and ground.
     Fig 3: Measuring Resistance Between Rear View Mirror C911-2 Circuit 31-AD15 (BK/OG) Harness Side And Ground

     Courtesy of FORD MOTOR CO.
   • Is the resistance less than 5 ohms? 
   1. Yes  : GO to K4.
   2. No  : REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
4. K4 CHECK CIRCUITS 8-MC8 (WH/RD) AND 9-MC8 (BN/RD) 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 C911 pins harness side; and between the navigation system module C4209 pins harness side and ground as follows:
     NAVIGATION SYSTEM MODULE C4209 PINS CHART
     
     

     Navigation System Module Pin	Rear View Mirror Pin	Circuit
     C4209-7	C911-9,	8-MC8 (WH/RD)
     C4209-19	C911-10	9-MC8 (BN/RD)

     Fig 4: Checking Circuits 8-MC8 (WH/RD) And 9-MC8 (BN/RD) For Open And Short To Ground

     Courtesy of FORD MOTOR CO.
   • Are the resistances less than 5 ohms between the navigation system module and the rear view mirror; and are the resistances greater than 10,000 ohms between the navigation system module and ground? 
   1. Yes  : GO to K5.
   2. No  : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
5. K5 CHECK CIRCUITS 8-MC8 (WH/RD) AND 9-MC8 (BN/RD) FOR A SHORT TO VOLTAGE 
   • Key in ON position.
   • Measure the voltage between the navigation system module C4209-7, circuit 8-MC8 (WH/RD), harness side and ground; and between the navigation system module C4209-19, 9-MC8 (BN/RD), harness side and ground.
     Fig 5: Checking Circuits 8-MC8 (WH/RD) And 9-MC8 (BN/RD) For Short To Voltage

     Courtesy of FORD MOTOR CO.
   • Is any voltage indicated? 
   1. Yes  : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
   2. No  : INSTALL a new rear view mirror. REFER to EXTERIOR TRIM . CLEAR the DTCs. REPEAT the self-test.
6. K6 CHECK FOR CORRECT NAVIGATION SYSTEM MODULE OPERATION 
   • Disconnect all navigation system module connectors.
   • Check for:
     • corrosion
     • pushed-out pins
   • Connect all 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? 
   1. Yes  : INSTALL a new navigation system module. REFER to NAVIGATION SYSTEM MODULE . TEST the system for normal operation.
   2. No  : The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.