P0A1F / INF129

P0A1F-129

Description
The battery smart unit (battery energy control module) sends HV battery voltage information to the hybrid vehicle control ECU via serial communication.

DTC Logic

DTC Detection Logic
The hybrid vehicle control ECU calculates the differences among the received HV battery voltage, boost converter voltage, and inverter voltage. If any of the differences exceed prescribed values, the hybrid vehicle control ECU determines that there is a malfunction in a battery smart unit circuit. When the hybrid vehicle control ECU detects a malfunction, it will illuminate the MIL and set a DTC.






Diagnostic Procedure

Step 1-3:

Step 3 (Continued):