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

The speed of the battery blower assembly is controlled by the hybrid vehicle control ECU. Battery blower assembly power is supplied from the FCTL terminal of the hybrid vehicle control ECU by the battery blower relay when it is turned on. The hybrid vehicle control ECU sends command signals (SI0, SI1 and SI2) to each battery blower assembly to get the fan speed corresponding to the HV battery temperature. Information of the voltage applied to each battery blower assembly (VM0, VM1 and VM2) is sent to the hybrid vehicle control ECU as a monitor signal via serial communication by the battery smart unit.

Fig 1: Identifying Battery Cooling Blower Assembly System Diagram
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DTC No.	DTC Detection Condition	Trouble Area
P0A84-123	Voltage at battery cooling blower assembly (VM0) is out of the predetermined range in proportion to the target control voltage (1 trip detection).	BATT FAN relay BATT FAN fuse Battery cooling blower assembly (No. 0) Battery cooling blower assembly (No. 1) Battery cooling blower assembly (No. 2) Battery smart unit Hybrid vehicle control ECU Harness or connector