Toyota Avalon (XX50): Collision detected or Collision Sensor Connection (Open) (P160600,P160604). Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Auxiliary Battery (P212012,...,P21382B). IG2 Signal Circuit Short

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Engine / Hybrid / Battery Control / Hybrid Control System / Collision detected or Collision Sensor Connection (Open) (P160600,P160604). Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Auxiliary Battery (P212012,...,P21382B). IG2 Signal Circuit Short

Collision detected or Collision Sensor Connection (Open) (P160600,P160604)

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU and airbag ECU assembly detect that a collision has occurred and shut off the system main relay.

The cause of this DTC may be one of the following:

Collision is detected
Detection sensor system malfunction
- Airbag system malfunction
- Hybrid vehicle control ECU malfunction
- Communication malfunction between airbag ECU assembly and hybrid vehicle control ECU
- Hybrid vehicle control ECU communication malfunction

DESCRIPTION

The hybrid vehicle control ECU receives a signal that indicates a collision from the airbag ECU assembly to detect a collision. After detecting a collision, the hybrid vehicle control ECU shuts off the high voltage systems for safety.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P160600	Collision detected or Collision Sensor Connection (Open)	Collision detection A block signal is received from the airbag ECU assembly. (1 trip detection logic)	Airbag ECU assembly Hybrid vehicle control ECU Airbag system	Does not come on	Master Warning Light: Comes on
P160604	Collision detected or Collision Sensor Connection (Open) System Internal Failure	Collision detection Multiple wiring malfunctions occur simultaneously. (1 trip detection logic)	Hybrid vehicle control ECU Airbag system	Does not come on	Master Warning Light: Comes on

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P160600

Collision detected or Collision Sensor Connection (Open)

Collision detection

A block signal is received from the airbag ECU assembly.

(1 trip detection logic)

Airbag ECU assembly
Hybrid vehicle control ECU
Airbag system

Does not come on

Master Warning Light:

Comes on

P160604

Collision detected or Collision Sensor Connection (Open) System Internal Failure

Collision detection

Multiple wiring malfunctions occur simultaneously.

(1 trip detection logic)

Hybrid vehicle control ECU
Airbag system

Does not come on

Master Warning Light:

Comes on

HINT:

If P160600 or P160604 is output, the hybrid system cannot be started unless the DTCs are cleared using the Techstream.

Related Data List

DTC No.	Data List
P160600	Airbag Status (Collision) Airbag Status (Normal)
P160604	Airbag Status (Collision) Airbag Status (Normal)

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

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream 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 Techstream on.
With power switch on (IG) and wait for 5 seconds or more.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform driving pattern again.

PROCEDURE

1.	CHECK VEHICLE FOR COLLISION DAMAGE

(a) Check the vehicle condition.

Result	Proceed to
The vehicle is not damaged.	A
The vehicle is damaged.	B

REPAIR VEHICLE

2.	CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

Powertrain > Hybrid Control > Trouble Codes

(d) Check for DTCs.

Result	Proceed to
Only DTC P160600 or P160604 is output, or DTCs other than in the table below are also output.	A
Any of the following DTCs including pending DTCs are also output.	B

Malfunction Content	Relevant DTC
Microcomputer malfunction	P060647	Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
	P060687	Hybrid/EV Powertrain Control Module Processor to Monitoring Processor Missing Message
	P060A29	Hybrid/EV Powertrain Control Module Monitoring Processor Signal Invalid
	P060A44	Hybrid/EV Powertrain Control Module Monitoring Processor Data Memory Failure
	P060A45	Hybrid/EV Powertrain Control Module Monitoring Processor Program Memory Failure
	P060A47	Hybrid/EV Powertrain Control Module Monitoring Processor Watchdog / Safety MCU Failure
	P060A49	Hybrid/EV Powertrain Control Module Monitoring Processor Internal Electronic Failure
	P060A87	Hybrid/EV Powertrain Control Module Processor from Monitoring Processor Missing Message
	P060B1C	Hybrid/EV Powertrain Control Module A/D Processing Voltage Out of Range
	P060B49	Hybrid/EV Powertrain Control Module A/D Processing Internal Electronic Failure
	P060B71	Hybrid/EV Powertrain Control Module A/D Processing Actuator Stuck
	P06881F	ECM/PCM Power Relay Sense Circuit Intermittent
	P1C9E9F	Hybrid/EV System Reset Stuck Off
	P1CE31C	Hybrid/EV Powertrain Control Module Monitoring Processor A/D Processing Voltage Out of Range
	P1CE349	Hybrid/EV Powertrain Control Module Monitoring Processor A/D Processing Internal Electronic Failure
	P1CE371	Hybrid/EV Powertrain Control Module Monitoring Processor A/D Processing Actuator Stuck

HINT:

P160600 or P160604 may be output as a result of the malfunction indicated by the DTCs above.

(e) Turn the power switch off.

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

3.	CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

Powertrain > Hybrid Control > Trouble Codes

(d) Check for DTCs.

Result	Proceed to
P160600 is output.	A
P160604 is output.	B

(e) Turn the power switch off.

CHECK AIRBAG SYSTEM

4.	CHECK DTC OUTPUT (HYBRID CONTROL, MOTOR GENERATOR)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

Powertrain > Hybrid Control > Trouble Codes

(d) Enter the following menus: Powertrain / Motor Generator / Trouble Codes.

Powertrain > Motor Generator > Trouble Codes

(e) Check for DTCs.

Result	Proceed to
DTCs of hybrid control system in the table below are output.	A
DTCs of motor generator control system in the table below are output.	B

System	Relevant DTC
Hybrid control system	P310711	Lost Communication with Airbag System Control Module Circuit Short to Ground (Low)
	P310715	Lost Communication with Airbag System Control Module Circuit Short to Auxiliary Battery or Open (High)
	U015187	Lost Communication with Restraints Control Module Missing Message
Motor generator control system	P312487	Lost Communication between Drive Motor "A" and HV ECU Missing Message

(f) Turn the power switch off.

GO TO DTC CHART (HYBRID CONTROL SYSTEM)

GO TO DTC CHART (MOTOR GENERATOR CONTROL SYSTEM)

Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Auxiliary Battery (P212012,...,P21382B)

DTC SUMMARY

MALFUNCTION DESCRIPTION

The hybrid vehicle control ECU calculates the accelerator pedal opening angle based on the output voltage of the main sensor (VPA) and sub sensor (VPA2) of the accelerator pedal sensor assembly. If the output voltage of either the main sensor (VPA) or sub sensor (VPA2) deviates, a malfunction will be detected.

The cause of this malfunction may be one of the following:

Accelerator pedal sensor assembly malfunction
Wire harness or connector malfunction
Hybrid vehicle control ECU malfunction

DESCRIPTION

The accelerator pedal position sensor is built into the accelerator pedal sensor assembly and detects how much the pedal is depressed. This is a non-contact sensor with Hall elements. There are 2 outputs from the sensor. One is used to detect the accelerator pedal position and the other is used as a confirmation to allow the detection of a malfunction in the sensor itself. Voltage is output from the accelerator pedal position sensor to terminals VPA and VPA2 of the hybrid vehicle control ECU. This voltage varies from 0 to 5 V in accordance with the accelerator pedal position. Terminal VPA2 is primarily used to detect a malfunction in the sensor itself. The hybrid vehicle control ECU determines the current accelerator pedal position and controls the hybrid control system based on signals received by terminals VPA and VPA2.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate
P212012	Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Auxiliary Battery	Short to +B in the main sensor circuit: The main sensor voltage is 4.8 V or more for 2 seconds. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P212014	Throttle/Pedal Position Sensor/Switch "D" Circuit Short to Ground or Open	Open or short to ground in the main sensor circuit: The main sensor voltage is 0.4 V or less for 0.5 seconds. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P21201C	Throttle/Pedal Position Sensor/Switch "D" Voltage Out of Range	Internal malfunction in the main sensor: Main sensor output changes rapidly (detected when there are no circuit malfunctions such as an open or short). (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P21201F	Throttle/Pedal Position Sensor/Switch "D" Circuit Intermittent	Main sensor circuit wiring malfunction or level is not stable: Main sensor voltage is 0.4 V or less or 4.8 V or more for a certain period of time. (Both of the following conditions are met: The main sensor voltage is 0.4 V or less for a certain period of time and 4.8 V or more for a certain period of time.) (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P212512	Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Auxiliary Battery	Short to +B in the sub sensor circuit: Main sensor is normal and sub sensor voltage is 4.8 V or more for 2 seconds. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P212514	Throttle/Pedal Position Sensor/Switch "E" Circuit Short to Ground or Open	Open or short to ground in the sub sensor circuit: The sub sensor voltage is 1.2 V or less for 0.5 seconds. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P21251C	Throttle/Pedal Position Sensor/Switch "E" Voltage Out of Range	Internal malfunction of the sub sensor: Sub sensor output changes rapidly (detected when there are no circuit malfunctions such as an open or short). (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P21251F	Throttle/Pedal Position Sensor/Switch "E" Circuit Intermittent	Sub sensor circuit wiring malfunction or level is not stable: When the main sensor circuit is normal, the sub sensor voltage is 1.2 V or less or 4.8 V or more for a certain period of time. (Both of the following conditions are met: Sub sensor voltage is 1.2 V or less for a certain period of time, and the main sensor is normal and sub sensor voltage is 4.8 V or more for a certain period of time.) (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P213800	Throttle/Pedal Position Sensor/Switch "D"/" E" Voltage Correlation	Difference between the main sensor value and sub sensor value is large. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on
P21382B	Throttle/Pedal Position Sensor/Switch "D"/"E" Signal Cross Coupled	Main or sub sensor circuit wiring malfunction: The difference in voltage between the main sensor and sub sensor is 0.02 V or less, or a low output malfunction continues in both the main and sub sensors for a certain period of time. (1 trip detection logic)	Wire harness or connector Accelerator pedal sensor assembly Hybrid vehicle control ECU	Comes on	Master Warning Light: Comes on

Related Data List

DTC No.	Data List
P212012	Accelerator Position Sensor No. 1 Voltage % Accelerator Position Sensor No. 2 Voltage %
P212014
P21201C
P21201F
P212512
P212514
P21251C
P21251F
P213800
P21382B

MONITOR DESCRIPTION

The hybrid vehicle control ECU calculates the differences of the voltage of main accelerator sensor and sub accelerator sensor. If the differences exceed prescribed values, the hybrid vehicle control ECU determines that there is a malfunction in the accelerator sensor circuit. If the hybrid vehicle control ECU detects this malfunction, it will illuminate the MIL and store a DTC.

MONITOR STRATEGY

Related DTCs	P2123 (INF P212012): Accelerator Pedal Position Sensor (APP Sensor) Sensor 1 Range Check (High voltage) P2122 (INF P212014): Accelerator Pedal Position Sensor (APP Sensor) Sensor 1 Range Check (Low voltage) P2121 (INF P21201C): Throttle/Pedal Position Sensor/Switch "D" Voltage Out of Range P2120 (INF P21201F): Accelerator Pedal Position Sensor (APP Sensor) Sensor 1 Range Check (Chattering) P2128 (INF P212512): Accelerator Pedal Position Sensor (APP Sensor) Sensor 2 Range Check (High voltage) P2127 (INF P212514): Accelerator Pedal Position Sensor (APP Sensor) Sensor 2 Range Check (Low voltage) P2126 (INF P21251C): Throttle/Pedal Position Sensor/Switch "E" Voltage Out of Range P2125 (INF P21251F): Accelerator Pedal Position Sensor (APP Sensor) Sensor 2 Range Check (Chattering) P2138 (INF P213800): Throttle/Pedal Position Sensor/Switch "D"/"E" Voltage Correlation P2138 (INF P21382B): Accelerator Pedal Position Sensor (APP Sensor) Correlation
Required sensors/components	Throttle/Pedal Position Sensor/Switch
Frequency of operation	Continuous
Duration	TMC's intellectual property
MIL operation	Immediately / 1 driving cycle
Sequence of operation	None

TYPICAL ENABLING CONDITIONS

The monitor will run whenever the following DTCs are not present	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

DTC P2122 (INF P212014) is not detected

DTC P2123 (INF P212012) is not detected

DTC P2120 (INF P21201F) is not detected

DTC P2127 (INF P212514) is not detected

DTC P2128 (INF P21251F) is not detected

DTC P2138 (INF P21382B) is not detected

DTC P2121 (INF P21201C) is not detected

DTC P2126 (INF P21251C) is not detected

DTC P2138 (INF P213800) 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

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream 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 Techstream on.
With power switch on (IG) and wait for 5 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.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform the normal judgment procedure again.

WIRING DIAGRAM

PROCEDURE

1.	READ VALUE USING TECHSTREAM (ACCELERATOR POSITION SENSOR NO. 1 VOLTAGE %, ACCELERATOR POSITION SENSOR NO. 2 VOLTAGE %)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Enter the following menus: Powertrain / Hybrid Control / Data List / Accelerator Position Sensor No. 1 Voltage %, Accelerator Position Sensor No. 2 Voltage %.

Powertrain > Hybrid Control > Data List

Tester Display
Accelerator Position Sensor No.1 Voltage %
Accelerator Position Sensor No.2 Voltage %

(d) Read the Data List.

Standard:

Tester Display	Accelerator Pedal Condition	Specified Condition
Accelerator Position Sensor No. 1 Voltage %	Not depressed	10 to 22%
	Fully depressed	52 to 90%
	Not depressed → Fully depressed → Not depressed (Accelerator pedal should be operated slowly)	Value changes progressively
Accelerator Position Sensor No. 2 Voltage %	Not depressed	24 to 40%
	Fully depressed	68 to 99%
	Not depressed → Fully depressed → Not depressed (Accelerator pedal should be operated slowly)	Value changes progressively

(e) Turn the power switch off.

CHECK FOR INTERMITTENT PROBLEMS

2.	CHECK CONNECTOR CONNECTION CONDITION (ACCELERATOR PEDAL SENSOR ASSEMBLY CONNECTOR)

(a) Check the connector connections and contact pressure of the relevant terminals for the accelerator pedal sensor assembly connector.

Click here

OK:

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

CONNECT SECURELY

3.	CHECK CONNECTOR CONNECTION CONDITION (HYBRID VEHICLE CONTROL ECU CONNECTOR)

Click here

CONNECT SECURELY

4.	CHECK HYBRID VEHICLE CONTROL ECU (CHECK VOLTAGE)

(a) Disconnect the A17 accelerator pedal sensor assembly connector.

(b) Turn the power switch on (IG).

Standard Voltage:

Tester Connection	Condition	Specified Condition
A17-4 (VCPA) - A17-5 (EPA)	Power switch on (IG)	4.5 to 5.5 V
A17-1 (VCP2) - A17-2 (EPA2)	Power switch on (IG)	4.5 to 5.5 V

*a	Front view of wire harness connector (to Accelerator Pedal Sensor Assembly)

(d) Turn the power switch off.

(e) Reconnect the A17 accelerator pedal sensor assembly connector.

GO TO STEP 6

5.	CHECK HYBRID VEHICLE CONTROL ECU (CHECK RESISTANCE)

(a) Disconnect the A17 accelerator pedal sensor assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A17-6 (VPA) - A17-5 (EPA)	Power switch off	28.00 to 41.61 kΩ
A17-3 (VPA2) - A17-2 (EPA2)	Power switch off	28.00 to 41.61 kΩ

*a	Front view of wire harness connector (to Accelerator Pedal Sensor Assembly)

REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY

GO TO STEP 7

6.	CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - ACCELERATOR PEDAL SENSOR ASSEMBLY)

(a) Disconnect the A23 hybrid vehicle control ECU connector.

(b) Disconnect the A17 accelerator pedal sensor assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A23-9 (VCPA) - Body ground	Power switch on (IG)	Below 1 V
A23-20 (EPA) - Body ground	Power switch on (IG)	Below 1 V
A23-8 (VCP2) - Body ground	Power switch on (IG)	Below 1 V
A23-18 (EPA2) - Body ground	Power switch on (IG)	Below 1 V

NOTICE:

Turning the power switch on (IG) with the hybrid vehicle control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

Rear view of wire harness connector

(to Hybrid Vehicle Control ECU)

Front view of wire harness connector

(to Accelerator Pedal Sensor Assembly)

(e) Turn the power switch off.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
A23-9 (VCPA) - A17-4 (VCPA)	Power switch off	Below 1 Ω
A23-20 (EPA) - A17-5 (EPA)	Power switch off	Below 1 Ω
A23-8 (VCP2) - A17-1 (VCP2)	Power switch off	Below 1 Ω
A23-18 (EPA2) - A17-2 (EPA2)	Power switch off	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
A23-9 (VCPA) or A17-4 (VCPA) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-20 (EPA) or A17-5 (EPA) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-8 (VCP2) or A17-1 (VCP2) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-18 (EPA2) or A17-2 (EPA2) - Body ground and other terminals	Power switch off	10 kΩ or higher

(g) Reconnect the A17 accelerator pedal sensor assembly connector.

(h) Reconnect the A23 hybrid vehicle control ECU connector.

REPLACE HYBRID VEHICLE CONTROL ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.	CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - ACCELERATOR PEDAL SENSOR ASSEMBLY)

(a) Disconnect the A23 hybrid vehicle control ECU connector.

(b) Disconnect the A17 accelerator pedal sensor assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
A23-30 (VPA) - Body ground	Power switch on (IG)	Below 1 V
A23-28 (VPA2) - Body ground	Power switch on (IG)	Below 1 V
A23-20 (EPA) - Body ground	Power switch on (IG)	Below 1 V
A23-18 (EPA2) - Body ground	Power switch on (IG)	Below 1 V

NOTICE:

Turning the power switch on (IG) with the hybrid vehicle control ECU connector disconnected causes other DTCs to be stored. Clear the DTCs after performing this inspection.

Rear view of wire harness connector

(to Hybrid Vehicle Control ECU)

Front view of wire harness connector

(to Accelerator Pedal Sensor Assembly)

(e) Turn the power switch off.

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

Standard Resistance (Check for Open):

Tester Connection	Condition	Specified Condition
A23-30 (VPA) - A17-6 (VPA)	Power switch off	Below 1 Ω
A23-20 (EPA) - A17-5 (EPA)	Power switch off	Below 1 Ω
A23-28 (VPA2) - A17-3 (VPA2)	Power switch off	Below 1 Ω
A23-18 (EPA2) - A17-2 (EPA2)	Power switch off	Below 1 Ω

Standard Resistance (Check for Short):

Tester Connection	Condition	Specified Condition
A23-30 (VPA) or A17-6 (VPA) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-20 (EPA) or A17-5 (EPA) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-28 (VPA2) or A17-3 (VPA2) - Body ground and other terminals	Power switch off	10 kΩ or higher
A23-18 (EPA2) or A17-2 (EPA2) - Body ground and other terminals	Power switch off	10 kΩ or higher

(g) Reconnect the A17 accelerator pedal sensor assembly connector.

(h) Reconnect the A23 hybrid vehicle control ECU connector.

REPLACE HYBRID VEHICLE CONTROL ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

IG2 Signal Circuit Short to Auxiliary Battery (P253012)

DESCRIPTION

The hybrid vehicle control ECU compares the IG2 signal to the IG control status signal sent from the certification ECU (smart key ECU assembly) to detect a stuck on malfunction of the IG2 signal.

HINT:

If DTC P253012 is stored, the power switch will turn off (READY off).

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Warning Indicate

P253012

IG2 Signal Circuit Short to Auxiliary Battery

The IG2 signal of the hybrid vehicle control ECU and the IG control status signal sent from the certification ECU (smart key ECU assembly) do not match.

(1 trip detection logic)

Auxiliary battery
Certification ECU (smart key ECU assembly)
Hybrid vehicle control ECU
ECM
IG2 NO. 1 relay
Wire harness or connector

Does not come on

Master Warning Light:

Comes on

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

Connect the Techstream to the DLC3.
Turn the power switch on (IG) and turn the Techstream 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 wait for 15 seconds or more.
Turn the power switch off and wait for 2 minutes or more.
Turn the power switch on (IG) and turn the Techstream on.
Enter the following menus: Powertrain / Hybrid Control / Utility / All Readiness.
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 or N/A, perform driving pattern again.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

Click here

PROCEDURE

1.	CHECK AUXILIARY BATTERY VOLTAGE

(a) Turn the power switch off and turn on the high beam headlights for 30 seconds. This will remove the surface charge from the auxiliary battery.

(b) Measure the auxiliary battery voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
Positive (+) auxiliary battery terminal - Negative (-) auxiliary battery terminal	20°C (68°F), Power switch off	12.0 V or higher

GO TO STEP 3

2.	CHARGE OR REPLACE AUXILIARY BATTERY

(a) Charge or replace the auxiliary battery.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

(e) Clear the DTCs.

Powertrain > Hybrid Control > Clear DTCs

(f) Turn the power switch off.

4.	CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Turn the power switch on (IG) and wait for 15 seconds or more.

(b) Turn the power switch off and wait for 2 minutes or more.

(d) Turn the power switch on (IG).

(e) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.

Powertrain > Hybrid Control > Trouble Codes

(f) Check for DTCs.

Result	Proceed to
P253012 is output.	A
P253012 is not output.	B

(g) Turn the power switch off.

CHECK FOR INTERMITTENT PROBLEMS

5.	CHECK DTC OUTPUT (HYBRID CONTROL)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Check for DTCs.

Powertrain > Hybrid Control > Trouble Codes

Result	Proceed to
U012987, U014087, U015187, U016487, U110787 or U117087 is output	A
Other than above	B

(e) Turn the power switch off.

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

6.	CHECK HYBRID VEHICLE CONTROL ECU

(a) Disconnect the A23 and G46 hybrid vehicle control ECU connectors.

*a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)

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

Condition:

Tester Connection	Condition
A23-3 (IG2) - G46-5 (E01)	Power switch off

Result	Proceed to
9 V or higher	A
Below 9 V	B

REPLACE HYBRID VEHICLE CONTROL ECU

CHECK ECM

(a) Disconnect the A23 and G46 hybrid vehicle control ECU connectors.

*a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)

(b) Disconnect the A19 ECM connector.

Condition:

Tester Connection	Condition
A23-3 (IG2) - G46-5 (E01)	Power switch off

(d) Reconnect the A19 ECM connector.

(e) Reconnect the A23 and G46 hybrid vehicle control ECU connectors.

Result	Proceed to
9 V or higher	A
Below 9 V	B

REPLACE ECM

8.	INSPECT RELAY (IG2 NO. 1)

(a) Remove the IG2 NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

*1	No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly
*2	IG2 NO. 1 Relay

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
3 - 5	Auxiliary battery voltage not applied between terminals 1 and 2	10 kΩ or higher
3 - 5	Auxiliary battery voltage applied between terminals 1 and 2	Below 1 Ω

REPLACE RELAY (IG2 NO. 1)

9.	CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU - IG2 NO. 1 RELAY)

(a) Disconnect the A23 hybrid vehicle control ECU connector.

(b) Remove the IG2 NO. 1 relay from the No. 1 engine room relay block and No. 1 junction block assembly.

Standard Voltage:

Tester Connection	Condition	Specified Condition
A23-3 (IG2) - Body ground	Power switch off	1 V or less

*a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU)

(d) Reinstall the IG2 NO. 1 relay.

(e) Reconnect the A23 hybrid vehicle control ECU connector.

CHECK FOR INTERMITTENT PROBLEMS

REPAIR OR REPLACE HARNESS OR CONNECTOR

Transmission Range Sensor "A" Circuit (PRNDL Input) Signal Compare Failure (P070562)

Hybrid/EV Battery Discharge Control Malfunction (P300000). Hybrid/EV Battery Control System Circuit Voltage Below Threshold (P300016). High Voltage Power Resource Circuit Short during Pre-Charge (P300

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