DTC B1668 Driver's Mirror Left/Right Circuit Failure
WARNING: This page is about a different car, the 1997 Lincoln Continental. However, it is still accessible from the selected car via links, so may be relevant.
- Rerun Self-Test - Inspect driver's mirror to ensure there are no obstructions. Rerun SELF-TEST. If Diagnostic Trouble Code (DTC) B1668 still exists, go to next step. If DTC B1668 does not exist, system is operating normally. No further action required.
- Driver Mirror Vertical Outputs Test - Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Enter DIAGNOSTIC DATA LINK. Enter DSM (Driver Seat Module). Enter ACTIVE COMMAND MODES. Select POWER MIRROR CONTROL. Command POWER MIRROR LEFT. Command POWER MIRROR RIGHT. Note mirror motion. Command POWER MIRROR LEFT. Note mirror motion. If mirror moves during last 2 movements, go to step 6). If mirror does not move during last 2 movements, go to next step.
- Remove door trim panel. Disconnect mirror connector and DSM connector C342. See Figure and Figure . Check voltage at mirror connector terminals No. 3 (Red wire) and No. 4 (Yellow/Red wire). If battery voltage exists, repair short to voltage in wire(s) and retest. If battery voltage does not exist, go to next step.
- Connect jumper wires from mirror connector terminals No. 3 (Red wire) and No. 4 (Yellow/Red wire) to ground. Check continuity between ground and DSM connector C342 terminals No. 2 (Red wire) and No. 16 (Yellow/Red wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open wire(s) and retest.
- Disconnect jumper wires. Check continuity between ground and DSM connector C342 terminals No. 2 (Red wire) and No. 16 (Yellow/Red wire). If resistance is 10,000 ohms or less, repair short to ground of wire(s) and retest. If resistance is more than 10,000 ohms, retest mirror. If mirror still does not operate, replace DSM and retest.
- Potentiometer Open Circuit Tests (Gray/Red Wire) - Check voltage by backprobing indicated wires at DSM connector C342. See POTENTIOMETER OPEN CIRCUIT TEST (DRIVER'S SIDE) TABLE . If voltage is greater than .5 volt on both circuits, go to next step. If voltage is less than .5 volt on both circuits, repair open in Gray/Red wire between driver's mirror and Driver Seat Module (DSM).
- Potentiometer Open Circuit Test (Red/White Wire) - Check voltage by backprobing DSM connector C342 terminal No. 9 (Red/White wire). If voltage is more than .5 volt, go to next step. If voltage is less than .5 volt, repair open Red/White wire or potentiometer. Retest system.
- Potentiometer Circuit Voltage Test - Check voltage by backprobing terminal No. 9 (Red/White wire) at DSM connector C342. If voltage is not .5-4.5 volts, go to next step. If voltage is .5-4.5 volts, replace mirror. Retest system.
- Potentiometer Voltage Test On Both Circuits - Check voltage by backprobing indicated wires at DSM connector C342. See POTENTIOMETER OPEN CIRCUIT TEST (DRIVER'S SIDE) TABLE. If voltage is not 4.5-5.0 volts on both circuits, replace DSM. Retest system. If voltage is 4.5-5.0 volts on both circuits, repair Gray wire between passenger's mirror and DSM connector C342 and retest.