BYD ATTO 3 (e-Platform 3.0) U025387 Loss Of Communication With Compressor

U025387 indicates a loss of communication between the vehicle’s control systems and the electric A/C compressor. The fault affects the electric air-conditioning and thermal-management system, which relies on communication between the compressor and vehicle control modules to regulate refrigerant circulation and cabin cooling. The BYD ATTO 3 uses BYD’s e-Platform 3.0 architecture, with this generation introduced from 2022 and continuing onward.

Symptoms

• Air conditioner does not produce cold air
• Compressor does not operate
• A/C cooling may be intermittent
• Climate control warning may be displayed
• Compressor status may show unavailable
• Cabin temperature remains higher than requested
• U025387 stored in a relevant control module
• Other communication or HVAC fault codes may be present

Possible Causes

• Loss of communication with the electric A/C compressor
• Compressor power supply fault
• Compressor ground connection fault
• Damaged compressor communication wiring
• Open or short circuit in the communication network
• Loose or damaged compressor connector
• Corroded or poorly seated terminals
• Internal compressor control-module failure
• Low or unstable 12V auxiliary voltage
• High-voltage system fault preventing compressor operation
• HVAC or thermal-management control-module fault
• CAN communication network fault

Diagnosis

Diagnosis should begin by confirming U025387 and performing a complete vehicle network scan for related power supply, communication, and HVAC faults. The compressor’s 12V and high-voltage supply status, ground circuit, communication lines, connector condition, network activity, and module availability should then be evaluated against manufacturer specifications.

The diagnostic direction should establish whether communication is being lost because of a power, wiring, network, compressor, or control-module problem before replacing the compressor.

Because the compressor operates as part of the vehicle’s high-voltage system, manufacturer safety procedures and appropriate EV service practices are essential. Workshop technicians across New Zealand frequently use factory repair procedures when diagnosing intermittent sensor and communication faults like this.

Accurately diagnosing this fault often requires manufacturer testing procedures, wiring diagrams, connector pinouts, specifications, and system calibration information. Access to the factory service manual significantly reduces diagnostic time and helps prevent unnecessary parts replacement.

Applicable Years

2022, 2023, 2024, 2025, 2026, onwards

To order the correct OEM Service and Repair Manual for your BYD ATTO 3, submit your request using the form below and our team will provide the ordering details.