DTC P0A84-123: EV Battery No. 1 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 electric vehicle battery assembly 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 No. 1 battery voltage sensor.

Fig 1: Identifying EV Battery Cooling Blower Assembly Control System Diagram
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DTC No.	INF Code	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. 1 integration relay Battery cooling blower assembly Electric vehicle battery assembly (No. 1 battery voltage sensor) Power management control ECU

HINT:

*: The above DTC can be stored while the battery cooling blower assembly operates. Therefore, the DTC will be detected when performing an Active Test of "Driving the Battery Cooling Fan".