P0AFA
P0AFA-123Description
The hybrid vehicle control ECU controls the SOC (state of charge) of the HV battery at a constant level while driving. The HV battery is composed of 34 modules, and each module consists of six 1.2 V cells in series. The battery smart unit monitors battery block voltage at 17 locations. Each battery block is composed of 2 modules in a set.
DTC Logic
DTC Detection Logic
The battery smart unit monitors a voltage of the battery blocks to detect an open malfunction in internal battery voltage sensor circuits of the battery smart unit and the wire harness between each battery block and battery smart unit. If a voltage at one of the battery blocks is below a standard level or of all the battery blocks is within a specified range, the battery smart unit judges that there is an open in the internal sensor circuit(s) or wire harness. The hybrid vehicle control ECU then illuminates the MIL and sets a DTC.
Diagnostic Procedure
Step 1-2:
Step 3-6:
