Engine-Codes - Mercury - B12BF Mercury

B12BF Mercury Code - Heated Backlight/Mirror Relay Drive Circuit Open Or Shorted To Ground

- Code Popularity: 600 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

|What are the Possible Causes of the Code B12BF Mercury?

  • Faulty Rear Window Defrost Relay
  • Rear Window Defrost Relay harness is open or shorted
  • Rear Window Defrost Relay circuit poor electrical connection
  • Faulty Rear Window Defrost Switch
  • Faulty Rear Window Defrost Grid
  • Faulty Heating Ventilation Air Conditioning (HVAC) Module

|How to Fix the B12BF Mercury Code?

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 Code B12BF Mercury?

Labor: 1.0

The cost to diagnose the B12BF Mercury code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

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|What are Code B12BF Mercury Possible Symptoms?

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

|What Does the B12BF Mercury Code Mean?

The Rear Window Defrost Relay receives power from the Battery Junction Box (BJB). When the rear window defrost switch is pressed to the ON position, the Heating Ventilation Air Conditioning (HVAC) Module activates the rear window defrost relay by grounding the circuit. When activated, the rear window defrost relay supplies 12 volts to the rear window defrost grid on the circuit. The rear window defrost grid is grounded through the circuit.

Heated Backlight/Mirror Relay Drive Circuit Open Or Shorted To Ground

|Need more Information on the B12BF Mercury Code?

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|Need Help with the B12BF Mercury Code?

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