Learn how to use CGDI CG100X Programmer to correct mileage on BYD Song Plus (2021-) R7F701621 models.
Protocol Overview by Chip Architecture
- 2021– 24C16 + R7F701621 Hybrid Cluster
- Verify that the detected IC chip model and current odometer values match the physical module.
- Operation Requirement:Both the 24C16 EEPROM and the R7F701621 MCU chips must be programmed together to adjust the mileage.
- 2023– 24C16 + R7F701621 Cluster
- Double-check chip identification and displayed mileage figures prior to writing data.
- Special Condition:If the CPU calculates the initial odometer value as 0, skip the modification process completely.
- Hybrid Left Body Control Module (BCM) – 25640 / 25256 Chips
- Strict Warning:Do NOT use an 8-pin test clip (solder-free adapter) for chip read or write operations. Direct soldering or dedicated sockets are required.
- Validate the exact chip part number before initiating any write commands.
- If the read mileage appears incorrect or miscalculated, halt the procedure and do not write new data.
