DTC P0A84-123: Hybrid Battery Pack Cooling Fan 1 Control Circuit Low: Description

The speed of the battery cooling blower assembly is controlled by the power management control ECU. Battery cooling blower assembly power is supplied when the FCTL terminal of the power management control ECU turns on the battery blower relay. The power management control ECU sends command signals (SI) to the battery cooling blower assembly to get the fan speed corresponding to the HV battery temperature. Information about the voltage applied to the battery cooling blower assembly (VM) is sent to the power management control ECU as a monitor signal using serial communication via the battery smart unit.

Fig 1: Identifying Battery Pack Cooling Fan 1 Control Circuit Operation
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DTC No.	DTC Detection Condition	Trouble Area
P0A84-123	When the output voltage of the battery cooling blower assembly (VM) is too low compared to the target control voltage range (1 trip detection)	Wire harness or connector No. 2 integration relay Battery cooling blower assembly Battery smart unit Power management control ECU