HYBRID CONTROL SYSTEM, Diagnostic DTC:P0AA073

DTC Code	DTC Name
P0AA073	Hybrid/EV Battery Positive and Negative Contactor Actuator Stuck Closed

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU detects a stuck closed malfunction of a system main relay on the positive (+) terminal side and negative (-) terminal side of the HV battery.

The cause of this malfunction may be one of the following:
- Voltage sensor (VH) malfunction
- Motor generator control ECU (MG ECU) malfunction
- Communication (wire harness) malfunction
- HV battery junction block assembly malfunction
- Hybrid vehicle control ECU malfunction
- HV battery junction block assembly malfunction
- Low voltage wire harness malfunction
- Low voltage connector malfunction

DESCRIPTION

Refer to the description for DTC P0AE411.

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This circuit uses the hybrid vehicle control ECU to monitor the system main relays and stops the system if a malfunction is detected in the relays, because it may be impossible to shut off the high-voltage system if any of the relays becomes stuck.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P0AA073	Hybrid/EV Battery Positive and Negative Contactor Actuator Stuck Closed	Even both of the system main relays (HV battery positive (+) and negative (-) terminal side) are turned off, the inverter voltage (VH) does not drop. (1 trip detection logic)	HV battery junction block assembly Inverter with converter assembly Hybrid vehicle control ECU Wire harness or connector	Does not come on	Master Warning Light: Comes on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P0AA073

Hybrid/EV Battery Positive and Negative Contactor Actuator Stuck Closed

Even both of the system main relays (HV battery positive (+) and negative (-) terminal side) are turned off, the inverter voltage (VH) does not drop.

(1 trip detection logic)

HV battery junction block assembly
Inverter with converter assembly
Hybrid vehicle control ECU
Wire harness or connector

Does not come on

Master Warning Light:

Comes on

Related Data List
DTC No.	Data List
P0AA073	Hybrid Battery Voltage VH-Voltage after Boosting VL-Voltage before Boosting

CONFIRMATION DRIVING PATTERN

Tech Tips

After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

Click here

Connect the GTS to the DLC3.
Turn the power switch on (IG) and turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the GTS on.
Turn the power switch on (READY) and wait for 3 minutes or more.

Tech Tips

According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes. If the difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V, the vehicle has returned to normal.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
Check the DTC judgment result.
Tech Tips
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows INCOMPLETE or N/A, perform driving pattern again.

WIRING DIAGRAM

Refer to the wiring diagram for the HV battery high-voltage line circuit.

Click here

CAUTION / NOTICE / HINT

CAUTION:

Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. 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.
Make sure to insulate the high-voltage connectors and terminals of the HV battery with insulating tape after removing it.

If the HV battery stored without insulating the connectors and terminals, electric shock or fire may result.

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
If the DTCs are cleared or the cable is disconnected and reconnected to the negative (-) auxiliary battery terminal before performing repairs, turning the power switch on (READY) may cause a malfunction. Do not turn the power switch on (READY).
Do not turn the power switch on (IG) with the service plug grip removed, as this may cause a malfunction.
If DTC P0AA073 is output, do not install the service plug grip before completing repair.

If the service plug grip is not removed, the HV battery will gradually discharge and the SOC will decrease.

Tech Tips

If DTC P0AA073 is output, the power switch cannot be turned on (READY).

PROCEDURE

CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control and Motor Generator / Trouble Codes.

Powertrain > Hybrid Control > Trouble Codes
Powertrain > Motor Generator > Trouble Codes

Check for DTCs.

Result

Result	Proceed to
P0AA073 only is output, or DTCs except the ones in the table below are also output.	A
DTCs of hybrid control system in the tables below are output.	B
DTCs of motor generator control system in the tables below are output.	C

Malfunction Content	System	Relevant DTC
Microcomputer malfunction	Hybrid control system	P060647	Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
		P060687	Hybrid/EV Powertrain Control Module Processor to Monitoring Processor Missing Message
		P060A47	Hybrid/EV Powertrain Control Module Monitoring Processor Watchdog / Safety MCU Failure
		P060A87	Hybrid/EV Powertrain Control Module Processor from Monitoring Processor Missing Message
		P0A1B49	Drive Motor "A" Control Module Internal Electronic Failure
		P1C9E9F	Hybrid/EV System Reset Stuck Off
	Motor generator control system	P0A1B1F	Generator Control Module Circuit Intermittent
		P0A1A47	Generator Control Module Watchdog / Safety μC Failure
		P0A1A49	Generator Control Module Internal Electronic Failure
		P1C2A1C	Generator A/D Converter Circuit Circuit Voltage Out of Range
		P1C2A49	Generator A/D Converter Circuit Internal Electronic Failure
		P1C2B1C	Drive Motor "A" Control Module A/D Converter Circuit Voltage Out of Range
		P1C2B49	Drive Motor "A" Control Module A/D Converter Circuit Internal Electronic Failure
		P1CAC49	Generator Position Sensor Internal Electronic Failure
		P1CAD49	Drive Motor "A" Position Sensor Internal Electronic Failure
		P1CAF38	Generator Position Sensor REF Signal Cycle Malfunction Signal Frequency Incorrect
		P1CB038	Drive Motor "A" Position Sensor REF Signal Frequency Incorrect
		P313383	Communication Error from Generator to Drive Motor "A" Value of Signal Protection Calculation Incorrect
		P313386	Communication Error from Generator to Drive Motor "A" Signal Invalid
		P313387	Communication Error from Generator to Drive Motor "A" Missing Message
Power source circuit malfunction	Motor generator control system	P06D61C	Generator Control Module Offset Power Circuit Voltage Out of Range
Power source circuit malfunction	Motor generator control system	P06B01C	Generator Control Module Position Sensor REF Power Source Circuit Voltage Out of Range
Communication system malfunction	Hybrid control system	P312387	Lost Communication with Drive Motor Control Module "A" from Hybrid/EV Control Module Missing Message
Sensor and actuator circuit malfunction	Hybrid control system	P0AD911	Hybrid/EV Battery Positive Contactor Circuit Short to Ground
		P0AD915	Hybrid/EV Battery Positive Contactor Circuit Short to Auxiliary Battery or Open
		P0ADD11	Hybrid/EV Battery Negative Contactor Circuit Short to Ground
		P0ADD15	Hybrid/EV Battery Negative Contactor Circuit Short to Auxiliary Battery or Open
		P0AE411	Hybrid/EV Battery Precharge Contactor Circuit Short to Ground
		P0AE415	Hybrid/EV Battery Precharge Contactor Circuit Short to Auxiliary Battery or Open
	Motor generator control system	P0A3F16	Drive Motor "A" Position Sensor Circuit Voltage Below Threshold
		P0A4B16	Generator Position Sensor Circuit Voltage Below Threshold
		P0A4B21	Generator Position Sensor Signal Amplitude < Minimum
		P0A4B22	Generator Position Sensor Signal Amplitude > Maximum
		P0C5013	Drive Motor "A" Position Sensor Circuit "A" Circuit Open
		P0C5016	Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Below Threshold
		P0C5017	Drive Motor "A" Position Sensor Circuit "A" Circuit Voltage Above Threshold
		P0C5A13	Drive Motor "A" Position Sensor Circuit "B" Circuit Open
		P0C5A16	Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Below Threshold
		P0C5A17	Drive Motor "A" Position Sensor Circuit "B" Circuit Voltage Above Threshold
		P0C6413	Generator Position Sensor Circuit "A" Circuit Open
		P0C6416	Generator Position Sensor Circuit "A" Circuit Voltage Below Threshold
		P0C6417	Generator Position Sensor Circuit "A" Circuit Voltage Above Threshold
		P0C6913	Generator Position Sensor Circuit "B" Circuit Open
		P0C6916	Generator Position Sensor Circuit "B" Circuit Voltage Below Threshold
		P0C6917	Generator Position Sensor Circuit "B" Circuit Voltage Above Threshold
System malfunction	Hybrid control system	P0C7600	Hybrid/EV Battery System Discharge Time Too Long
		P0D2D1C	Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
		P1C8349	High Voltage Power Resource Circuit Voltage Sensor after Boosting Malfunction
	Motor generator control system	P0D2D16	Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Below Threshold
		P0D2D17	Drive Motor "A" Inverter Voltage Sensor (VH) Circuit Voltage Above Threshold
		P1CB69E	Drive Motor "A" Inverter Voltage Sensor (VH) Stuck On

Tech Tips

P0AA073 may be output as a result of the malfunction indicated by the DTCs above.

The chart above is listed in inspection order of priority.
Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

Turn the power switch off.

GO TO DTC CHART (HYBRID CONTROL SYSTEM) Click here

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM) Click here

CHECK FREEZE FRAME DATA (HYBRID CONTROL)

Connect the GTS to the DLC3.
Turn the power switch on (IG).
Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Read the freeze frame data of DTC P0AA073.

Powertrain > Hybrid Control > DTC(P0AA073) > Freeze Frame Data

Tester Display
VL-Voltage before Boosting
VH-Voltage after Boosting

Note

As freeze frame data is stored immediately before and after a DTC is stored, make sure to only read the values for the moment the DTC was stored ("0(s)").

Result

Result	Proceed to
Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is less than 76 V.	A
Difference between "VL-Voltage before Boosting" and "VH-Voltage after Boosting" is 76 V or more.	B

Tech Tips

If VH-Voltage after Boosting is output even when an off command is being sent to the system main relay (positive side), P0AA073 is output. If the difference between the "VL-Voltage before Boosting" and the "VH-Voltage after Boosting" is large, it is determined that there is an inverter (VH sensor) malfunction.

Turn the power switch off.

REPLACE INVERTER WITH CONVERTER ASSEMBLY Click here

CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

Check the connector connections and contact pressure of the relevant terminals for the hybrid vehicle control ECU connectors.

Tech Tips

Click here

for LHD

for RHD

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

Result

Proceed to
OK
NG

GO TO STEP 5 Click here

CONNECT SECURELY

Result

Proceed to
NEXT

CHECK CONNECTOR CONNECTION CONDITION (FLOOR WIRE CONNECTOR)

*A	for LHD
*B	for RHD

Check the connection condition of the MF2 or MF1 floor wire connector and the contact pressure of each terminal. Check the terminals for deformation, and check the connector for water ingress and foreign matter.

Tech Tips

Click here

OK
- The connector is connected securely.
- The terminals are not deformed and are connected securely.
- No water or foreign matter in the connector.

Result

Result	Proceed to
OK	A
NG (The connector is not connected securely.)	B
NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.)	C

GO TO STEP 8 Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR Click here

CONNECT SECURELY

Result

Proceed to
NEXT

GO TO STEP 8 Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result

Proceed to
NEXT

CHECK CONNECTOR CONNECTION CONDITION (HV BATTERY JUNCTION BLOCK ASSEMBLY CONNECTOR)

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 (IG), unless instructed by the repair manual because this may cause a malfunction.
Remove the No. 1 HV battery cover panel RH.

Tech Tips

Click here
Check the connector connections and contact pressure of the relevant terminals of the M37 HV battery junction block assembly connector.

Tech Tips

Click here

OK

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

Install the No. 1 HV battery cover panel RH.

Result

Proceed to
OK
NG

GO TO STEP 10 Click here

CONNECT SECURELY

Result

Proceed to
NEXT

CHECK GROUND WIRE CONNECTION CONDITION (SMR ACTIVATION LOW-VOLTAGE CIRCUIT)

Check the installation condition of the ground wire MD.

OK
The ground wire MD is securely installed.

Result

Proceed to
OK
NG

GO TO STEP 12 Click here

CONNECT SECURELY

Result

Proceed to
NEXT

CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - HV BATTERY JUNCTION BLOCK ASSEMBLY)

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 (IG), unless instructed by the repair manual because this may cause a malfunction.
Remove the No. 1 HV battery cover panel RH.

Tech Tips

Click here
Disconnect the M37 HV battery junction block assembly connector.
Disconnect the F2 hybrid vehicle control ECU connector.

Front view of wire harness connector

(to Hybrid Vehicle Control ECU)

Front view of wire harness connector

(to HV Battery Junction Block Assembly)

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

Standard Resistance (Check for Open)

Tester Connection	Condition	Specified Condition
F2-16 (SMRB) - M37-1 (SMRB)	Power switch off	Below 1 Ω
F2-13 (SMRG) - M37-4 (SMRG)	Power switch off	Below 1 Ω
F2-15 (SMRP) - M37-2 (SMRP)	Power switch off	Below 1 Ω

Standard Resistance (Check for Short)

Tester Connection	Condition	Specified Condition
F2-16 (SMRB) and M37-1 (SMRB) - Body ground and other terminals	Power switch off	10 kΩ or higher
F2-13 (SMRG) and M37-4 (SMRG) - Body ground and other terminals	Power switch off	10 kΩ or higher
F2-15 (SMRP) and M37-2 (SMRP) - Body ground and other terminals	Power switch off	10 kΩ or higher

Reconnect the F2 hybrid vehicle control ECU connector.
Reconnect the M37 HV battery junction block assembly connector.

Install the No. 1 HV battery cover panel RH.

Result

Proceed to
OK
NG

GO TO STEP 14 Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result

Proceed to
NEXT

CHECK HARNESS AND CONNECTOR (HV BATTERY JUNCTION BLOCK ASSEMBLY - BODY GROUND)

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 (IG), unless instructed by the repair manual because this may cause a malfunction.
Remove the No. 1 HV battery cover panel RH.

Tech Tips

Click here
Disconnect the M37 HV battery junction block assembly connector.

*a	Front view of wire harness connector (to HV Battery Junction Block Assembly)

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

Standard Resistance

Tester Connection	Condition	Specified Condition
M37-3 (GND) - Body ground	Power switch off	Below 1 Ω

Reconnect the M37 HV battery junction block assembly connector.

Install the No. 1 HV battery cover panel RH.

Result

Proceed to
OK
NG

GO TO STEP 16 Click here

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result

Proceed to
NEXT

INSPECT HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB, SMRG, SMRP)

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 (IG), unless instructed by the repair manual because this may cause a malfunction.
Remove the No. 1 HV battery cover panel RH.

Tech Tips

Click here
Disconnect the M37 HV battery junction block assembly connector.

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

Component without harness connected

(HV Battery Junction Block Assembly)

Standard Resistance

Tester Connection	Condition	Specified Condition
M37-1 (SMRB) - M37-3 (GND)	-40 to 80°C (-40 to 176°F)	20.6 to 40.8 Ω
M37-4 (SMRG) - M37-3 (GND)	-40 to 80°C (-40 to 176°F)	20.6 to 40.8 Ω
M37-2 (SMRP) - M37-3 (GND)	-40 to 80°C (-40 to 176°F)	140 to 290 Ω

Reconnect the M37 HV battery junction block assembly connector.

Install the No. 1 HV battery cover panel RH.

Result

Proceed to
OK
NG

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

CHECK HV BATTERY JUNCTION BLOCK ASSEMBLY (SMRB, SMRG, SMRP)

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 (IG), unless instructed by the repair manual because this may cause a malfunction.
Remove the No. 1 HV battery cover panel RH.

Tech Tips

Click here
Disconnect the 2 HV floor under wire connectors from the HV battery junction block assembly.
Disconnect the 2 HV battery high voltage connectors from the HV battery junction block assembly.

Note

Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.

*a	Component without harness connected (HV Battery Junction Block Assembly)

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

Standard Resistance

Tester Connection	Condition	Specified Condition
S4-1 (CBI) - A-1 (+)	Power switch off	10 kΩ or higher

Tech Tips

If a system main relay is stuck closed, inspect the HV battery junction block assembly without removing it from the vehicle, in order to keep the relay closed.
If the result of reading the freeze frame data is A, the HV battery junction block assembly must be replaced. Measuring resistance can determine that this is either a present or past malfunction.

*a	Component without harness connected (HV Battery Junction Block Assembly)

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

Standard Resistance

Tester Connection	Condition	Specified Condition
S3-1 (CEI) - z12-1 (-)	Power switch off	10 kΩ or higher

Tech Tips

If a system main relay is stuck closed, inspect the HV battery junction block assembly without removing it from the vehicle, in order to keep the relay closed.
If the result of reading the freeze frame data is A, the HV battery junction block assembly must be replaced. Measuring resistance can determine that this is either a present or past malfunction.
If the resistance is between 24.3 and 29.7 Ω, it can be determined that SMRP is stuck closed.

Reconnect the 2 HV battery high voltage connectors.
Reconnect the 2 HV floor under wire connectors.

Install the No. 1 HV battery cover panel RH.

Result

Result	Judgment	Proceed to
OK	Past malfunction	A
NG	Present malfunction	B

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY Click here

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

Tech Tips

Click here

Result

Proceed to
NEXT

GO TO STEP 21 Click here

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

Tech Tips

Click here

Result

Proceed to
NEXT

GO TO STEP 21 Click here

REPLACE HV BATTERY JUNCTION BLOCK ASSEMBLY

Tech Tips

Click here

Result

Proceed to
NEXT

CHECK HYBRID VEHICLE CONTROL ECU (CHECK FOR NORMAL OPERATION)

Install the service plug grip.
Turn the power switch on (IG).
Clear the DTCs.

Powertrain > Hybrid Control > Clear DTCs
Turn the power switch off and wait for 30 seconds or more.
Turn the power switch on (READY).

Enter the following menus: Powertrain / Hybrid Control / Data List / Hybrid Battery Voltage, VL-Voltage before Boosting.

Powertrain > Hybrid Control > Data List

Tester Display
VL-Voltage before Boosting
Hybrid Battery Voltage

According to the display on the GTS, read the Data List and monitor the values of "Hybrid Battery Voltage" and "VL-Voltage before Boosting" for 3 minutes.

Result

Result	Proceed to
Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is always less than 100 V.	A
Difference between "Hybrid Battery Voltage" and "VL-Voltage before Boosting" is 100 V or more.	B

Turn the power switch off.

END

REPLACE HYBRID VEHICLE CONTROL ECU AND HV BATTERY JUNCTION BLOCK ASSEMBLY HYBRID VEHICLE CONTROL ECU: Click here
REPLACE HYBRID VEHICLE CONTROL ECU AND HV BATTERY JUNCTION BLOCK ASSEMBLY HV BATTERY JUNCTION BLOCK ASSEMBLY: Click here