DTC P0A96-11: Hybrid/EV Battery Cooling Fan 2 Circuit Short to Ground; DTC P0A96-4B: Hybrid/EV Battery Cooling Fan 2 Over Temperature [10/2022 - ]: Description

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The No. 2 battery cooling blower assembly speed is controlled by the battery voltage sensor. Power is supplied to the No. 2 battery cooling blower assembly when the MREL terminal of the hybrid vehicle control ECU turns on the IGCT NO. 1 relay. The battery voltage sensor sends command signals (SI1) to the No. 2 battery cooling blower assembly to adjust the fan speed to an appropriate speed for the HV battery temperature. The frequency (FP1) of the No. 2 battery cooling blower assembly is sent to the hybrid vehicle control ECU via the battery voltage sensor as a monitor signal using CAN communication.

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DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate	DTC Output from	Priority	Note
P0A96-11	Hybrid/EV Battery Cooling Fan 2 Circuit Short to Ground	Both of the following conditions are met: The speed calculated based on the No. 2 battery cooling blower assembly output frequency is not within the target control speed range. The No. 2 battery cooling blower assembly speed is excessively low when a certain level of speed is requested (possibility of an open or short to ground in connected circuits, or motor locking). (2 trip detection logic)	Battery voltage sensor No. 2 Battery cooling blower assembly BATT FAN relay Wire harness or connector	Comes on	Master Warning: Comes on	Hybrid Control	A	SAE Code: P0A99
P0A96-4B	Hybrid/EV Battery Cooling Fan 2 Over Temperature	Both of the following conditions are met: The HV battery temperature is high and the speed calculated based on the No. 2 battery cooling blower assembly output frequency is not within the target control speed range. The HV battery temperature is high and the No. 2 battery cooling blower assembly speed is excessively low when a certain level of speed is requested (possibility of an open or short to ground in connected circuits, or motor locking). (1 trip detection logic)	Battery voltage sensor No. 2 Battery cooling blower assembly BATT FAN relay Wire harness or connector	Comes on	Master Warning: Comes on	Hybrid Control	A	SAE Code: P0A99

HINT:

"Hybrid/EV Battery Cooling Fan 2 Frequency" is detected when the No. 2 battery cooling blower assembly is operating and its value changes in proportion to the No. 2 battery cooling blower assembly speed.