Engine-Codes - Lincoln - B1234 LINCOLN

B1234 LINCOLN - Mirror Switch Invalid Code

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

B1234 LINCOLN Possible Causes

  • Faulty Mirror Switch
  • Mirror Switch harness is open or shorted
  • Mirror Switch circuit poor electrical connection
  • Faulty Driver Door Module (DDM)

How is the B1234 LINCOLN code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the B1234 LINCOLN code

Labor: 1.0

The cost to diagnose the B1234 LINCOLN code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

B1234 LINCOLN Meaning

Under normal operation, the exterior mirror control switch receives power and ground from the circuit. The exterior mirror control switch uses circuits to send input signals to the Driver Door Module (DDM). The DDM controls the Left (LH) exterior mirror motor movement by supplying the appropriate power and ground to circuits. The DDM communicates with the Driver Seat Module (DSM) through the Medium-Speed Controller Area Network (MS-CAN) whenever the DDM receives an input signal from the exterior mirror control switch for the Right (RH) mirror. The DSM controls the RH exterior mirror motor movement by supplying the appropriate power and ground.
The memory mirror system uses feedback potentiometers, located in the LH and RH exterior mirrors, in order to track the movement of the LH and RH exterior mirror motors. The DDM supplies the LH and RH exterior mirror feedback potentiometer reference voltage and ground through circuits. The DDM receives feedback from the LH and RH exterior mirror feedback potentiometer through left/right and up/down circuits.

More Information

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