AutoCodes - OBDII Code List - B12C4 MERCURY

B12C4 MERCURY - Mirror Turn Indicator Circuit Short

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

B12C4 MERCURY Possible Causes

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

How do I fix code B12C4 MERCURY?

Check 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.
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Tech Notes

B12C4:11 Mirror Turn Indicator Circuit Short To Ground
B12C4:15 Mirror Turn Indicator Circuit Short To Battery Or Open

Cost of diagnosing the B12C4 MERCURY code

Labor: 1.0

The cost of diagnosing the B12C4 MERCURY code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

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

B12C4 MERCURY Description

The Driver Door Module (DDM) monitors the Mirror Turn Indicator Circuit. The DDM sets the OBDII code when the Mirror Turn Indicator Circuit is not to factory specifications.
OBDII Code B12c4 Mercury - Mirror Turn Indicator Circuit Short -

More Information

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