Engine-Codes - Generic - B12A2

B12A2 - Passenger Blend Door Actuator Slow Or Door Obstructed

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

B12A2 Possible Causes

  • 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 is the B12A2 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 B12A2 code

Labor: 1.0

The cost to diagnose the B12A2 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)

B12A2 Meaning

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.

More Information

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Information for specific makes

  • B12A2 FORD Passenger Blend Door Actuator Slow Or Door Obstructed
  • B12A2 LINCOLN Passenger Blend Door Actuator Slow Or Door Obstructed
  • B12A2 MERCURY Passenger Blend Door Actuator Slow Or Door Obstructed

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