AU
U1332-00

DTC U1332-00 indicates the airbag control unit (SRS ECU) receives an abnormal or timed-out vehicle speed signal via the body CAN bus (B-CAN) — Qin Plus

Safety System

DTC U1332-00 indicates the airbag control unit (SRS ECU) receives an abnormal or timed-out vehicle speed signal via the body CAN bus (B-CAN).

This fault occurs when the SRS module fails to receive a valid vehicle speed data frame from the instrument cluster or ABS/ESP module within the predetermined cycle, preventing the airbag system from determining collision severity based on real-time vehicle speed.

This safety system communication fault compromises the collision safety strategy, potentially causing airbag deployment timing deviations during high-speed collisions or false deployments during low-speed collisions.

The U1332-00 fault code on the Qin Plus indicates a medium-severity communication problem where the airbag control unit does not receive a valid vehicle speed signal over the body CAN bus. Common causes include a faulty instrument cluster or gateway CAN module, or a damaged CAN transceiver inside the SRS control unit. The recommended fix is to visit an authorised dealer for diagnosis and repair. Typical repair cost data is available from recorded cases.
5
Cases Logged
5
Causes
Likely Causes — Qin Plus
  • 1Internal fault in the instrument cluster CAN communication module or gateway prevents transmission of the vehicle speed signal to the B-CAN network.
  • 2The internal CAN transceiver in the SRS control unit is damaged and cannot receive or decode the vehicle speed data frame.
  • 3B-CAN network wiring physical layer fault, including water ingress and oxidation at G10/M40 connectors, harness damage causing short/open circuits, or excessive contact resistance.
  • 4Abnormal network termination resistance (standard value approximately 60 Ω, which the SRS module and instrument cluster module provide in parallel), causing signal reflection or attenuation.
  • 5Use of a non-genuine instrument cluster or SRS module during accident repairs, resulting in a CAN communication protocol mismatch or incompatible software version.
What To Do
  • 1
    Use the dedicated diagnostic tool to read the fault code and record freeze frame data. Confirm the vehicle speed, time, and environmental conditions when the fault occurred.
  • 2
    Visually check if the instrument cluster vehicle speed display is normal. Determine whether the fault is a signal source issue (no instrument cluster display) or a transmission issue (instrument cluster normal but SRS reports a fault).
  • 3
    Measure the CAN bus voltage at the diagnostic port: CAN-H should be 2.5-2.7V and CAN-L should be 2.3-2.5V. Confirm the bus physical layer base voltage is normal.
  • 4
    Disconnect SRS module connector G10 and measure the terminating resistance between terminals G10-2 (B-CAN-L) and G10-3 (B-CAN-H). The standard value is approximately 60Ω (two 120Ω resistors in parallel). If the resistance is abnormal, inspect the wiring section by section.
  • 5
    Check the SRS module power supply (battery positive, ignition positive) and ground circuits. Verify the voltage drop is less than 0.1V to rule out power supply interference as the cause of communication interruption.
  • 6
    Use an oscilloscope to monitor the B-CAN waveform and check for data frame loss, bit errors, ACK errors, or signal distortion. Focus inspection on the G10 connector and the wiring harness bend at the left A-pillar.
  • 7
    Check CAN wiring insulation. Measure CAN-H and CAN-L resistance to ground and power. Inspect for water-induced corrosion or wiring harness wear causing intermittent short circuits.
  • 8
    Perform a substitution test: Replace the instrument cluster or SRS module with a unit of the same model. Observe if the fault code transfers to confirm the faulty component.
  • 9
    After repairing the wiring or replacing the faulty module, clear the fault code and perform a road test to verify the SRS system receives the vehicle speed signal in real time and the warning lamp turns off.
Real-World Cases
BYD DTC AI Analysis

BYD S6 instrument cluster CAN module damage caused loss of vehicle speed signal

✓
The airbag warning light illuminated on the instrument cluster. The scanner retrieved DTC U1332-00. The speedometer displayed normal readings while driving, but the SRS system reported a vehicle speed fault. The technician checked B-CAN network communication with an oscilloscope and found it normal, but found that speed data frames sent from the instrument cluster to the SRS were occasionally lost. The technician traced the fault to the internal CAN communication module in the instrument cluster and replaced the assembly with a genuine part. Fault resolved.
Original source ↗
BYD DTC AI Analysis

BYD NEV precharge resistor failure caused CAN network failure

✓
The vehicle presented with a powertrain fault and multiple CAN communication DTCs including U1332-00. Diagnosis found a damaged front-end pre-charge resistor in the high-voltage battery pack, disrupting communication between the BMS and vehicle controller and affecting vehicle speed signal transmission across the CAN network. Replaced the pre-charge resistor and performed cell balancing on the battery pack. Network communication returned to normal and the U1332 DTC cleared.
Original source ↗
BYD DTC AI Analysis

Protocol mismatch caused by non-genuine instrument cluster in accident-repaired vehicle

✓
After accident repairs, the airbag warning light stayed on. Retrieved DTC U1332-00. Inspection found an aftermarket instrument cluster installed during the repair. The speedometer displayed correctly, but the cluster’s CAN protocol differed from the SRS module’s, so the SRS could not parse the vehicle speed data. Replaced the cluster with an OEM unit and reconfigured the SRS system parameters. Fault resolved.
Original source ↗
BYD DTC AI Analysis

BYD S6 left A-pillar wiring harness damage causing intermittent CAN-L short circuit

✓
On starting the vehicle after parking, the airbag warning light illuminated with DTC U1332-00 stored. Inspection found water stains on the G10 connector. Further investigation revealed the wiring harness beneath the left A-pillar had insulation damage from a previous accident repair, contacting the body metal and causing an intermittent short to ground on the CAN-L line. Repaired the damaged wiring, cleaned oxidation from the connector and applied waterproofing. Fault cleared.
Original source ↗
BYD DTC AI Analysis

Internal transceiver damage in SRS control unit caused vehicle-wide communication failure

✓
Multiple warning lights (ABS, SRS, ESP) illuminated simultaneously while driving. Scanner retrieved communication fault codes including U1332-00 and U0140. Using segmented troubleshooting, disconnected the SRS module; other systems returned to normal. Confirmed faulty CAN transceiver inside the SRS control unit continuously transmitting error frames and paralyzing the B-CAN network. Replaced the SRS control unit, recoded and matched it to the vehicle. Fault completely resolved.
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.