AU
B2A2C92

This DTC indicates the front passenger side temperature flap actuator (air mix flap motor) cannot reach the target position or the position feedback signal is abnormal — Qin Plus

Thermal Management System

This DTC indicates the front passenger side temperature flap actuator (air mix flap motor) cannot reach the target position or the position feedback signal is abnormal.

The integrated Body Control Module (BCM) drives this stepper/DC motor via the LIN bus or PWM signal to adjust the air mix flap opening and control the front passenger outlet temperature. "Cannot reach position" means the motor fails to reach the target angle within the set time (typically 3-5 seconds), or the position sensor feedback voltage deviates from the expected value by more than the threshold (generally >5%).

This fault disables front passenger temperature adjustment (no hot or cold air).

Severe cases may cause abnormal flap noise or trigger air conditioning system protection mode, but typically do not affect vehicle driving safety.

The B2A2C92 fault code on the Qin Plus indicates the front passenger temperature flap actuator cannot reach its target position or has abnormal position feedback. Severity is medium: it can stop passenger-side hot/cold adjustment but usually does not affect driving safety. Common causes include a failed actuator motor or poor wiring/fuse socket contact causing voltage drop. Visit an authorised dealer for diagnosis and repair. Typical repair cost data is available.
3
Cases Logged
5
Causes
Likely Causes — Qin Plus
  • 1Internal damage to the temperature damper actuator motor (worn gear set, seized motor rotor, or excessively worn carbon brushes), causing insufficient driving force to overcome damper resistance.
  • 2Poor wiring contact or open circuit, especially excessive pin clearance or deformation at the air conditioning fuse socket (such as IF03) in the instrument panel distribution box, causing excessive power supply voltage drop (common after tapping power for aftermarket accessories like GPS units and dash cams).
  • 3Air flap mechanism jammed (broken flap shaft, deformed plastic flap, detached foam seal causing binding, or foreign object blocking the air duct), triggering motor stall protection.
  • 4Integrated Body Control Module (BCM) internal driver chip fault or abnormal LIN bus communication, causing loss of motor drive signal or position sampling circuit fault.
  • 5Temperature blend door position sensor (potentiometer) signal drift or open circuit causes abnormal feedback voltage, leading the BCM to incorrectly determine the door is not in position.
What To Do
  • 1
    Connect the VDS diagnostic tool, read all fault codes, and record freeze frame data. Confirm if related fault codes such as B2A2C14 (short to ground/open circuit) accompany B2A2C92, and check if the BCM software version requires an update.
  • 2
    Check the air conditioning system fuses (IF03, etc.) in the instrument panel power distribution box. Specifically inspect the fuse holder terminals for excessive clearance, looseness, or burn damage from aftermarket equipment (GPS, dash cams) tapping power. Measure the voltage drop across the fuse; it must be <0.1V.
  • 3
    Remove the passenger-side glovebox or lower dashboard trim panel. Visually inspect the air mix door actuator (usually located on the right side of the HVAC assembly) for physical damage, connector oxidation, or backed-out terminals. Measure the motor power supply (constant 12V), ground (<0.5Ω), and LIN wire/PWM signal wire continuity.
  • 4
    Disconnect the motor connector and use an oscilloscope or multimeter to measure the BCM control signal. If the signal is normal, connect an external 12V power supply directly to the motor to verify it operates through its full range of travel. Listen for abnormal gear slipping noise. Measure the position sensor feedback voltage; the voltage must change linearly with rotation (0.5-4.5V).
  • 5
    Remove the actuator and manually rotate the air flap shaft to check if the internal HVAC mechanism is binding or loose. Check if the air flap sealing strip has detached and obstructs movement. If necessary, use a borescope to inspect the air duct for foreign objects.
  • 6
    If the actuator is faulty, replace it with an OEM temperature blend door actuator (align to the zero position during installation; some models require a diagnostic tool for blend door position learning/calibration). Clear the fault code and test the adjustment function across all positions from full cold to full hot to verify normal operation.
Real-World Cases
BYD DTC AI Analysis

Excessive clearance in fuse holder pins caused multiple motors to fail

✓
A 2018 Qin PRO DM owner reported the AC temperature and mode could not be adjusted. VDS scanning revealed motor DTCs B2A2C92 (passenger side temperature control motor position not reachable) and B2A2A92 (mode motor position not reachable). Inspection found a GPS retrofit tapping power from the air conditioning fuse. The GPS fuse blade was wider than OEM spec, spreading the IF03 fuse holder terminals and increasing contact resistance. Although the fuse appeared intact, insufficient voltage caused multiple air door actuators to fault simultaneously. Repaired the fuse holder terminals, restored the factory fuse, removed the added wiring harness, and cleared the fault.
Original source ↗
BYD DTC AI Analysis

Temperature blend door actuator internal gears slipping

✓
A 2019 Song MAX had constant cold air from the passenger side AC; the temperature could not be adjusted. The scan tool retrieved DTC B2A2C92. Live data showed target position at 100% (full heat) while actual position remained at 0% (full cold). Measured the actuator power supply, ground, and signal lines — all normal. Applied external power: the motor ran but the damper shaft did not turn, indicating worn plastic gears slipping inside the actuator. Replaced the passenger side temperature damper actuator. The actuator now follows temperature adjustment commands normally, the DTC cleared, and temperature adjustment function restored.
Original source ↗
BYD DTC AI Analysis

HVAC damper shaft binding, causing motor stall

✓
A 2017 Qin EV300 developed a clicking noise after the AC turned on, followed by passenger-side temperature control failure and DTC B2A2C92. Technicians removed the HVAC assembly and found the blend door shaft seized at the bushings from dust accumulation—the blend door had remained stationary for an extended period because the vehicle was always driven in recirculation mode with the temperature set to low. The actuator motor tried to drive the shaft but stalled against the resistance, eventually overheating and storing the fault. They cleaned the shaft bushings, applied specialized silicone-based grease, manually verified smooth operation, and reinstalled the original actuator (motor undamaged). Fault resolved. Advise the owner to regularly switch between temperature modes to prevent blend door mechanism seizure.
Other Qin Plus Fault Codes
B1108For the BYD Song MAX (2017–2019), DTC B1108 indicates a short circuit in the PM2.5 air quality detection module (dust sensor) or its wiring harness. The sensor uses laser scattering to detect in-cabin and outside PM2.5 concentrations and transmits data to the HVAC ECU via the LIN bus or an analog signal. Short circuit conditions include: 1) Sensor power supply wire (+5V/+12V) shorted to ground 2) Signal wire shorted to power or ground 3) Short circuit in the sensor's internal photoelectric detection circuit This fault prevents the automatic climate control from switching between fresh air and recirculation based on air quality. The system enters fail-safe mode (typically forced recirculation). Severe short-circuit current can destroy the HVAC ECU sampling circuit. The system classifies this as a Level 3 severe fault and restricts vehicle operation to prevent electrical fires or controller damage. For other BYD models (such as the Qin EV, E5, and Song DM), B1108 indicates a driver-side sunload sensor fault, reflecting differences in DTC definitions across models.B110913DTC B110913 indicates an open signal circuit for the PM2.5 rapid detector (in-cabin air quality sensor). This sensor typically mounts inside the air conditioning system intake duct. It monitors in-cabin PM2.5 concentration in real time and provides data to the automatic air conditioning system for intelligent control of the air purification function. The BYD diagnostic protocol uses sub-code '13' to specifically indicate an open signal circuit. Although this fault theoretically affects a comfort feature, BYD Qin series vehicles classify it as a Level 3 (severe) fault. This classification occurs because the air conditioning system interacts with the battery thermal management system (e.g., monitoring battery cooling intake air quality). The fault can disable the automatic air conditioning mode and prevent the air purification function from operating. In extreme cases, it affects the battery compartment intake air quality assessment, triggering the 'repair immediately' strategy.B110BDTC B110B indicates a fault in the internal air pump (sampling pump) of the PM2.5 air quality detector. This pump draws cabin or outside air into the PM2.5 sensor detection chamber, enabling the laser scattering sensor to measure real-time particulate matter concentration. The air conditioning controller (or BCM) sets this DTC upon detecting an open or short circuit in the pump drive circuit, or abnormal current caused by a seized pump motor. This fault disables the "Green Clean" system, causes the instrument cluster air quality display to read abnormally or disappear, and disables the automatic fresh air/recirculation switching function. It does not affect the vehicle powertrain or core thermal management functions.B173A1ADTC B173A1A indicates the right middle-row side airbag (typically located on the side of the right second-row seat or inside the C-pillar trim panel) igniter circuit resistance measures 0 Ω. In the Supplemental Restraint System (SRS), normal airbag igniter resistance ranges between 2.0 and 5.0 Ω. A resistance of 0 Ω indicates a short to ground or a short between circuit wires, preventing the Airbag Control Unit (ACU) from establishing a normal monitoring circuit. This safety-critical fault prevents the airbag from deploying during a collision, continuously illuminates the instrument panel SRS warning lamp, and may force the entire airbag system into fail-safe mode.B173BDTC B173B indicates an abnormal electric A/C compressor speed feedback signal or a communication fault between the compressor controller and the motor. In BYD new energy models (e.g., Tang, Song, Qin, and Yuan series), this DTC belongs to the HVAC subsystem within the Body Control system and specifically involves the electric compressor closed-loop control circuit. The ECU sets this DTC when the compressor controller (IPM) fails to receive a valid pulse signal from the Hall speed sensor for more than 3 continuous seconds, or when the deviation between the detected actual speed and the target commanded speed exceeds the calibrated threshold (typically >500 rpm). This fault forces the A/C system into fail-safe mode and stops compressor operation. Symptoms include a complete lack of cooling, intermittent cooling, or a sharp decrease in cooling performance. The instrument cluster A/C warning lamp may also illuminate. Prolonged operation with this fault can degrade high-voltage system insulation or cause controller overcurrent damage.
Common problems reported for Qin Plus →Qin Plus overview →
Data confidence: Official This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.