Engine-Codes - Generic - B12B3

B12B3 Code - Blend Door Actuator Drive Circuit Shorted To Battery Voltage

- Code Popularity: 488 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

|What are the Possible Causes of the B12B3 Code?

  • Stuck or damaged linkage or door
  • Faulty Blend Door Actuator
  • Blend Door Actuator harness is open or shorted
  • Blend Door Actuator circuit poor electrical connection
  • Electronic Manual Temperature Control (EMTC) Module
  • Electronic Automatic Temperature Control (EATC) Module

|How to Fix the B12B3 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 B12B3 code?

Labor: 1.0

The cost to diagnose the B12B3 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.

|What are B12B3 code possible symptoms?

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

|What Does the B12B3 Code Mean?

Under normal operation, to rotate the blend door actuator clockwise, the Electronic Manual Temperature Control (EMTC) Module or Electronic Automatic Temperature Control (EATC) Module supplies voltage to the blend door actuator motors through the door actuator feed A circuits and supplies ground through the door actuator feed B circuits. To rotate the blend door actuator counterclockwise, the EMTC module or EATC module reverses the voltage and ground circuits.
The blend door actuator feedback resistors are supplied a ground from the EMTC module or EATC module by the blend door actuator return circuits and a 5-volt reference voltage on the blend door actuator reference circuits. The EMTC module or EATC module reads the voltage on the blend door actuator feedback circuits to determine the blend door actuator position by the position of the actuator feedback resistor wiper arm.

Blend Door Actuator Drive Circuit Shorted To Battery Voltage

|Need more information with the B12B3 code?

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|B12B3 code information for specific makes

  • B12B3 FORD Blend Door Actuator Drive Circuit Shorted To Battery Voltage
  • B12B3 LINCOLN Blend Door Actuator Drive Circuit Shorted To Battery Voltage
  • B12B3 MERCURY Blend Door Actuator Drive Circuit Shorted To Battery Voltage

|Need help with a B12B3 code?

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