Pinpoint Test I: Navigation System Does Not Operate Correctly - The Audio Unit Is Inoperative
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.
- I1 CHECK THE RECORDED DTCS FROM THE NAVIGATION SYSTEM MODULE
- Use the recorded results from the navigation system module self-test.
- Are any DTCs recorded?
- Yes : For DTC B2208, GO to I2. For all other DTCs, REFER to the NAVIGATION SYSTEM MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX .
- No : GO to PINPOINT TEST E to continue diagnosis of the video circuits.
- I2 CHECK CIRCUITS 1772 (VT) AND 1499 (PK/LG) FOR VOLTAGE
- Key in OFF position.
- Disconnect: Audio Unit C2253a.
- Key in ON position.
- Measure the voltage between the audio unit C2253a pin 1, circuit 1772 (VT), harness side and ground; and between the audio unit C2253a pin 2, circuit 1499 (PK/LG), harness side and ground.
- Are the voltages greater than 10 volts?
- Yes : GO to I3.
- No : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
- I3 CHECK CIRCUIT 694 (BK/LG) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between the audio unit C2253a pin 13, circuit 694 (BK/LG) harness side and ground; and between the audio unit C2253a pin 24, circuit 694 (BK/LG), harness side and ground.
- Are the resistances less than 5 ohms?
- Yes : GO to I4.
- No : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
- I4 CHECK CIRCUITS 1532 (DB/WH) AND 1533 (DG/OG) FOR AN OPEN AND A SHORT TO GROUND
- Disconnect: Navigation System Module C4209.
- Disconnect: Audio Unit C2253b.
- Measure the resistances between the navigation system module C4209 pins, harness side and the audio unit C2253b pins, harness side; and between the navigation system module C4209 pins, harness side and ground as follows:NAVIGATION SYSTEM MODULE PIN SPECIFICATION
Navigation System Module Pin Audio Unit Pin Circuit C4209 pin 5 C2253b pin 7 1532 (DB/WH) C4209 pin 17 C2253b pin 14 1533 (DG/OG) - Are the resistances less than 5 ohms between the navigation system module and the audio unit, and greater than 10,000 ohms between the navigation system module and ground?
- Yes : GO to I5.
- No : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
- I5 CHECK CIRCUITS 1532 (DB/WH) AND 1533 (DG/OG) FOR A SHORT TO BATTERY
- Key in ON position.
- Measure the voltage between the navigation system module C4209 pin 5, circuit 1532 (DB/WH), harness side and ground; and between the navigation system module C4209 pin 17, circuit 1533 (DG/OG), harness side and ground.
- Is any voltage indicated?
- Yes : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
- No : GO to I6.
- I6 SUBSTITUTE THE AUDIO UNIT
- Substitute a known good audio unit.
- Repeat the navigation system module self-test.
- Is DTC B2208 present?
- Yes : REINSTALL the original audio unit. GO to I7.
- No : REMOVE the audio unit and SEND it to an authorized Ford audio system repair facility. REFER to AUDIO UNIT . CLEAR the DTCs. REPEAT the self-test.
- I7 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 . CLEAR the DTCs. REPEAT the self-test.
- 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.