Toyota Corolla Cross: Hybrid/EV Battery Voltage High (P31B300)

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU uses the inverter voltage to monitor the HV battery voltage and detect malfunctions.

The cause of this malfunction may be the following:

Inverter with converter assembly malfunction (Boost converter system)

• VL sensor malfunction
• VH sensor malfunction

HV battery system

• Battery ECU assembly malfunction
• HV battery malfunction

DESCRIPTION

The hybrid vehicle control ECU uses the inverter voltage to monitor the HV battery voltage and detect malfunctions.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate	Note
P31B300	Hybrid/EV Battery Voltage High	The inverter voltage exceeds the threshold. (1 trip detection logic)	Inverter with converter assembly Battery ECU assembly HV battery	Comes on	Master Warning Light: Comes on	SAE Code: P31B3

MONITOR DESCRIPTION

The hybrid vehicle control ECU monitors the cell overcharge signal. If the hybrid vehicle control ECU detects an abnormality in the sensor signal, the hybrid vehicle control ECU will illuminate the MIL and set a DTC.

MONITOR STRATEGY

Related DTCs	P31B3 (INF P31B300): Hybrid/EV Battery Voltage high
Required sensors/components	Battery ECU assembly
Frequency of operation	Continuous
Duration	TMC's intellectual property
MIL operation	1 driving cycle
Sequence of operation	None

TYPICAL ENABLING CONDITIONS

The monitor will run whenever the following DTCs are not stored	TMC's intellectual property
Other conditions belong to TMC's intellectual property	-

TYPICAL MALFUNCTION THRESHOLDS

TMC's intellectual property

-

COMPONENT OPERATING RANGE

Hybrid vehicle control ECU

P31B3 (INF P31B300) is not detected

CONFIRMATION DRIVING PATTERN

HINT:

• After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

  Click here

• When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

  Click here

1. Connect the GTS to the DLC3.
2. Turn the ignition switch to ON and turn the GTS on.
3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
4. Turn the ignition switch off and wait for 2 minutes or more.
5. Turn the ignition switch to ON and turn the GTS on.
6. Turn the ignition switch to ON (READY) and wait for 30 seconds or more. [*1]

   HINT:

   [*1] : Normal judgment procedure.

   The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

7. Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
8. Check the DTC judgment result.

   HINT:

   • 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, perform the normal judgment procedure again.

WIRING DIAGRAM

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

Click here

CAUTION / NOTICE / HINT

CAUTION:

Refer to the precautions before inspecting high voltage circuit.

Click here

NOTICE:

• After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

  Click here

• When disconnecting and reconnecting the auxiliary battery

  HINT:

  When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

  Click here

HINT:

• P31B300 may be output as a result of the malfunction indicated by the DTCs in table below.
  1. The chart above is listed in inspection order of priority.
  2. 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.)

Malfunction Content	System	Relevant DTC
Sensor and actuator circuit malfunction	Hybrid control system	P0D2D1C	Drive Motor "A" Inverter Voltage Sensor Voltage Out of Range
		P0E311C	Boosting Converter Voltage Sensor "A" Voltage Out of Range
		P1C2D62	Hybrid/EV Battery "A" Voltage Sensor/Boosting Converter Voltage Sensor "A" Signal Compare Failure
	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
		P0D2D1F	Drive Motor "A" Inverter Voltage Sensor(VH) Circuit Intermittent
		P0E3116	DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Below Threshold
		P0E3117	DC/DC Converter Voltage Sensor "A" (VL) Circuit Voltage Above Threshold
		P0E311F	DC/DC Converter Voltage Sensor "A"(VL) Circuit Intermittent
		P0E5717	DC/DC Converter Voltage Sensor "A"(VL) Circuit Voltage Above Threshold

PROCEDURE

1.	READ VALUE USING GTS (HYBRID/EV BATTERY VOLTAGE)

(a) Read the Data List.

Powertrain > HV Battery > Data List

Tester Display
Hybrid/EV Battery Voltage

NOTICE:

Be sure not to measure when the ignition switch is ON (READY).

(b) Make a note of the data list item "Hybrid/EV Battery Voltage".

(c) Turn the ignition switch off.

NEXT

2.	CHECK HV BATTERY

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

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

(b) Disconnect the HV battery high voltage connectors. NOTICE: Insulate each disconnected high-voltage connector with insulating tape. Wrap the connector from the wire harness side to the end of the connector.

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

Standard Voltage:

Tester Connection	Condition
z26-1 (+) - z23-1 (-)	Ignition switch off

CAUTION:

Do not allow the probes of the electrical tester to contact each other during this inspection.

(d) Check the value in the data list "Hybrid/EV Battery Voltage" and the hybrid battery voltage value that was actually measured.

Result	Proceed to
When the difference between "Hybrid/EV Battery Voltage" in the Data List and the measurement value of the HV battery voltage is 5 V or more.	A
Other than above	B

(e) Reconnect the HV battery high voltage connectors.

B

GO TO STEP 4

A

3.	REPLACE BATTERY ECU ASSEMBLY

Click here

NEXT

REPLACE HV BATTERY

4.	CHECK FREEZE FRAME DATA (HYBRID/EV BATTERY VOLTAGE)

(a) Read the freeze frame data of DTC P31B300.

Powertrain > Hybrid Control > DTC(P31B300) > Freeze Frame Data

Tester Display
Hybrid/EV Battery Voltage

Result	Proceed to
"Hybrid/EV Battery Voltage" is less than 292 V.	A
Other than above	B

(b) Turn the ignition switch off.

A

REPLACE INVERTER WITH CONVERTER ASSEMBLY

B

5.	REPLACE BATTERY ECU ASSEMBLY

Click here

NEXT

REPLACE HV BATTERY

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