HYBRID BATTERY SYSTEM, Diagnostic DTC:P0AAE-123, P0AAF-123

DTC Code	DTC Name
P0AAE-123	Hybrid Battery Pack Air Temperature Sensor "A" Circuit Low
P0AAF-123	Hybrid Battery Pack Air Temperature Sensor "A" Circuit High

DESCRIPTION

The inlet air temperature sensor (battery) is mounted on the HV battery. The resistance of the sensor varies in accordance with changes in the intake air temperature. The characteristics of the inlet air temperature sensor are the same as those of the battery temperature sensor Click here. The battery smart unit uses signals from the inlet air temperature sensor to control the air volume of the battery cooling blower assembly.

DTC No.	DTC Detection Condition	Trouble Area
P0AAE-123 P0AAF-123	When the temperature indicated by the inlet air temperature sensor is lower than a predetermined limit (open circuit) or is higher than a predetermined limit (short circuit)	Hybrid battery thermistor Battery smart unit Wire harness or connector Hybrid battery junction block assembly

DTC No.

DTC Detection Condition

Trouble Area

P0AAE-123

P0AAF-123

When the temperature indicated by the inlet air temperature sensor is lower than a predetermined limit (open circuit) or is higher than a predetermined limit (short circuit)

Hybrid battery thermistor
Battery smart unit
Wire harness or connector
Hybrid battery junction block assembly

Tech Tips

After confirming that DTC P0AAE-123 or P0AAF-123 is output, use the intelligent tester to check "Inhaling Air Temp" in the HV ECU data list.

Displayed Temperature	Malfunction
-45°C (-49°F) or less	Open or +B short circuit
95°C (203°F) or more	GND short

WIRING DIAGRAM

Refer to the wiring diagram for DTC P0A9C-123 Click here.

INSPECTION PROCEDURE

CAUTION:

Before inspecting the high-voltage system, take safety precautions to prevent electrical shocks, such as wearing insulated gloves and removing the service plug grip. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work Click here.

Tech Tips

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

Note

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Click here.

PROCEDURE

CHECK DTC OUTPUT (HV)

Connect the intelligent tester to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / DTC.

Check if DTCs are output.

Result

Result	Proceed to
P0AFC-123 is not output.	A
P0AFC-123 is also output.	B

Turn the power switch off.

GO TO DTC CHART Click here

CHECK INSTALLATION OF INLET AIR TEMPERATURE SENSOR

CAUTION:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.

Note

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

Check installation of inlet air temperature sensor

Check the connections of connector z10 of the battery smart unit.

OK
The connectors are connected securely and there are no contact problems.

Result

Result	Proceed to
NG	B
OK	Go to next step

Visually check the installation condition of the inlet air temperature sensor.

OK
The inlet air temperature sensor is installed in the correct location and its claws are engaged securely.

Result

Result	Proceed to
The inlet air temperature sensor is installed in the correct location and its claws are engaged securely.	A
Claws are damaged.	C
Inlet air temperature sensor is not installed correctly, but claws are not damaged.	D

CONNECT SECURELY

REPLACE HYBRID BATTERY THERMISTOR Click here

INSTALL PARTS CORRECTLY

CHECK HYBRID BATTERY THERMISTOR (INLET AIR TEMPERATURE SENSOR AND BATTERY TEMPERATURE SENSOR)

CAUTION:

Be sure to wear insulated gloves.

Check that the service plug grip is not installed.

Note

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.
Disconnect connectors i1 and z10 from the battery smart unit.

Text in Illustration
*a	Rear view of wire harness connector (to Battery Smart Unit)

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
z10-1 (TCO) - z10-7 (GCO)	0°C (32°F)	26.7 to 27.8 kΩ
	25°C (77°F)	9.9 to 10.1 kΩ
	40°C (104°F)	5.73 to 5.92 kΩ

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
z10-1 (TCO) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-1 (TCO) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-7 (GCO) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-7 (GCO) - i1-8 (GND)	Power switch off	10 kΩ or higher

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Switch Condition	Specified Condition
z10-6 (TBO) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-6 (TBO) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-12 (GBO) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-12 (GBO) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-5 (TB1) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-5 (TB1) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-11 (GB1) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-11 (GB1) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-4 (TB2) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-4 (TB2) - i1-8 (GND)	Power switch off	10 kΩ or higher
z10-10 (GB2) - i1-4 (IGCT)	Power switch off	10 kΩ or higher
z10-10 (GB2) - i1-8 (GND)	Power switch off	10 kΩ or higher

Connect the battery smart unit connectors.

Click here

REPLACE BATTERY SMART UNIT Click here

CHECK HARNESS AND CONNECTOR (INLET AIR TEMPERATURE SENSOR AND BATTERY TEMPERATURE SENSOR)

CAUTION:

Be sure to wear insulated gloves and protective goggles.

Check that the service plug grip is not installed.

Note

After removing the service plug grip, do not turn the power switch on (READY), unless instructed by the repair manual because this may cause a malfunction.

Check the wire harness and connectors of the battery temperature sensor and inlet air temperature sensor for abnormalities by sight and touch.

Specified Condition
There are no open or short circuits in the wire harness and connectors. There are no short circuits to other wire harnesses.

REPAIR HARNESS OR CONNECTOR

REPLACE HYBRID BATTERY THERMISTOR Click here