Toyota Corolla Cross: Ignition Switch Circuit Short to Ground or Open (P253014)

DESCRIPTION

If the engine stop and start ECU receives the off signal from the ignition or starter switch assembly*1 or certification ECU (smart key ECU assembly)*2 when communication with the ECM is normal, the engine stop and start ECU will output DTC P253014.

• *1: w/o Smart Key System
• *2: w/ Smart Key System

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Warning Indicate	Note
P253014	Ignition Switch Circuit Short to Ground or Open	All of the following conditions are met for 10 seconds or more (1 trip detection logic): Ignition switch off signal is input. Communication with the ECM is normal. Ignition switch (communication) ON	Wire harness or connector EFI-MAIN NO. 1 relay IGP relay Power distribution box assembly (IGR NO. 1 relay)*1 Ignition or starter switch assembly*2 Certification ECU (Smart key ECU assembly)*1 Engine stop and start ECU	Does not come on	Does not come on (For Mexico Models: Blinks)	SAE Code: P2531

• *1: w/ Smart Key System
• *2: w/o Smart Key System

CONFIRMATION DRIVING PATTERN

HINT:

• If the cable is disconnected from the auxiliary battery terminal, stop and start control is prohibited until refresh charge is completed.

  In this case, let the vehicle idle to complete the refresh charge. The refresh charge is complete when the Data List item "Status of Battery Charge Control" changes from "Refresh Charge Mode". (Usually, by idling the engine for 5 to 60 minutes with the auxiliary battery fluid temperature at 11°C (52°F) or higher, the refresh charge will be completed.)

• If the GTS is not available and the Data List item "Status of Battery Charge Control" cannot be checked, charge the auxiliary battery by idling the engine for approximately 5 to 60 minutes or driving the vehicle, and then drive the vehicle and check that stop and start control operates.

  If the engine is started with the hood open, the system determines that a jump start has occurred. Therefore, make sure that the hood is closed before starting the engine and driving the vehicle.

• After the refresh charge completes, turn the ignition switch off, wait for at least 30 seconds, and then start the engine again. If the vehicle enters refresh charge mode again while the engine is idling, the initial refresh charge did not properly complete, so wait for the refresh charge to complete.
• Allow the engine to idle for 3 minutes after it is warmed up and check that the engine idle speed is within 50 rpm of the target idle speed.

CONFIRMATION AFTER TROUBLESHOOTING

(a) Clear the DTCs.

Powertrain > Stop and Start > Clear DTCs

(b) Start the engine and warm it up.

(c) Drive the vehicle at 7 km/h (4 mph) or more.

CAUTION:

When performing Confirmation Driving Pattern, obey all speed limits and traffic laws.

(d) Depress the brake pedal and stop the vehicle.

(e) Keep the engine stopped by stop and start control for 1 second or more. (Keep the shift lever in D.)

(f) Release the brake pedal with the shift lever in D to start the engine.

HINT:

If the engine cranks slowly when the engine is restarted, it can be determined that the auxiliary battery voltage is low.

(g) Check that DTCs are not output.

Powertrain > Stop and Start > Trouble Codes

STOP AND START SYSTEM OPERATION CHECK

Click here

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

• Before replacing the engine stop and start ECU, read the number of starter operations and write it into a new engine stop and start ECU.

  Click here

• After replacing the engine stop and start ECU, perform learning of the external backup boost converter (eco run vehicle converter assembly).

  Click here

• After replacing the engine stop and start ECU or air conditioning amplifier assembly, reset and perform learning of the air conditioning information in the engine stop and start ECU.

  Click here

• When the engine stop and start ECU or oil pump with motor assembly is replaced, check the oil pump with motor assembly.

  Click here

• When the ECM is replaced on a vehicle with a non-specified auxiliary battery, it is necessary to perform auxiliary battery type switching.

  Click here

• Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

• Using the GTS, read the freeze frame data before troubleshooting. System condition information is recorded as freeze frame data the moment a DTC is stored. This information can be useful when troubleshooting.

  Click here

• For wire harness and connector inspection procedures and precautions, refer to " "
• DTCs for the stop and start system are not cleared even if the malfunction has been repaired. After repairing the malfunction, be sure to clear the DTCs.

PROCEDURE

1.	READ VALUE USING GTS (IG SWITCH)

(a) Enter the following menus.

Powertrain > Stop and Start > Data List

Tester Display
IG Switch

(b) Read the value displayed on the GTS.

Tester Display	Result	Proceed to
IG Switch	ON	A
IG Switch	OFF	B

A

USE SIMULATION METHOD TO CHECK

B

2.	CHECK ENGINE STOP AND START ECU (IGP TERMINAL VOLTAGE)

*a

Component with harness connected (Engine Stop and Start ECU)

-

-

(a) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
I230-18 (IGP) - Body ground	Ignition switch ON	9.5 to 14 V

NG

GO TO STEP 8

OK

3.	CHECK ENGINE STOP AND START ECU (+B TERMINAL VOLTAGE)

*a

Component with harness connected (Engine Stop and Start ECU)

-

-

(a) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
A169-1 (+B) - Body ground	Ignition switch ON	9.5 to 14 V

OK

REPLACE ENGINE STOP AND START ECU

NG

4.	CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - EFI-MAIN NO. 1 RELAY)

(a) Disconnect the A169 engine stop and start ECU connector.

(b) Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
A169-1 (+B) - EFI-MAIN NO.1 relay terminal 3	Always	Below 1 Ω
A169-1 (+B) - Body ground and other terminals	Always	10 kΩ or higher
EFI-MAIN NO.1 relay terminal 3 - Body ground and other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.	INSPECT EFI-MAIN NO.1 RELAY

Click here

NG

REPLACE EFI-MAIN NO. 1 RELAY

OK

6.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 1 RELAY - ECM)

(a) Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block.

(b) Disconnect the A47 ECM connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
EFI-MAIN NO.1 relay terminal 1 - A47-15 (MREL)	Always	Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

7.	CHECK HARNESS AND CONNECTOR (EFI-MAIN NO. 1 RELAY - POWER SOURCE)

(a) Remove the EFI-MAIN NO. 1 relay from the No. 1 engine room relay block.

*1 Component without harness connected (No. 1 Engine Room Relay Block) *a EFI-MAIN NO. 1 Relay Terminal

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
EFI-MAIN NO.1 relay terminal 2 - Body ground	Always	9.5 to 14 V
EFI-MAIN NO.1 relay terminal 5 - Body ground	Always	9.5 to 14 V

OK

GO TO ECM POWER SOURCE CIRCUIT

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.	CHECK HARNESS AND CONNECTOR (ENGINE STOP AND START ECU - POWER DISTRIBUTION BOX ASSEMBLY (IGR-NO. 2 RELAY))

(a) Disconnect the I230 engine stop and start ECU connector.

(b) Disconnect the 8B power distribution box assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
I230-21 (IGR) - 8B-39	Always	Below 1 Ω
I230-21 (IGR) - Body ground and other terminals	Always	10 kΩ or higher
8B-39 - Body ground and other terminals	Always	10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

9.	CHECK VEHICLE SPECIFICATION

(a) Check the vehicle specification

Result	Proceed to
w/ Smart Key System	A
w/o Smart Key System	B

A

GO TO SMART KEY SYSTEM

B

10.	INSPECT POWER DISTRIBUTION BOX ASSEMBLY (IGR-NO. 2 RELAY)

(a) Disconnect the 8B and 8J power distribution box assembly connector.

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
8B-39 (voltmeter positive (+) lead) - 8B-24 (voltmeter negative (-) lead)	Auxiliary battery voltage not applied to terminals 8J-1 (auxiliary battery positive (+)) and 8B-36 (auxiliary battery negative (-))	Below 1 V

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
8B-39 (voltmeter positive (+) lead) - 8B-24 (voltmeter negative (-) lead)	Auxiliary battery applied to terminals 8J-1 (auxiliary battery positive (+)) and 8B-36 (auxiliary battery negative (-))	11 to 14 V

NG

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

OK

11.	CHECK HARNESS AND CONNECTOR (IGP-MAIN RELAY - POWER SOURCE)

(a) Remove the IGP-MAIN relay from the No. 1 engine room relay block.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
IGP-MAIN relay terminal 5 - Body ground	Always	9.5 to 14 V

OK

GO TO ECM POWER SOURCE CIRCUIT

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

READ NEXT: