DTC B2278: Engine/Power Switch Malfunction [12/2019 - 11/2023]: Procedure
- READ VALUE USING GTS (START SWITCH1, START SWITCH2)
- Read the Data List according to the display on the GTS.
Body Electrical > Power Source Control > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note Start Switch1 Power switch 1 status OFF or ON OFF: Power switch not pressed
ON: Power switch pressed- If the power switch is pressed for a short time, the display may not change.
- Use this item to determine if the power switch input signal is malfunctioning.
Start Switch2 Power switch 2 status OFF or ON OFF: Power switch not pressed
ON: Power switch pressed- Backup for power switch 1. However, when the power switch is pressed and held, the control functions only when both power switch 1 and 2 are normal.
- Behaves the same way as power switch 1.
Body Electrical > Power Source Control > Data List
Tester Display Start Switch1 Start Switch2 OK
The GTS display changes correctly in response to the power switch operation.
Result
Proceed to OK NG
Result:
NG
See step 3
Result:
OK
See step 2
- Read the Data List according to the display on the GTS.
- READ VALUE USING GTS (START SWITCH1, START SWITCH2)
- According to the display on the GTS, read the Data List while wiggling the wire harness.
Body Electrical > Power Source Control > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note Start Switch1 Power switch 1 status OFF or ON OFF: Power switch not pressed
ON: Power switch pressed- If the power switch is pressed for a short time, the display may not change.
- Use this item to determine if the power switch input signal is malfunctioning.
Start Switch2 Power switch 2 status OFF or ON OFF: Power switch not pressed
ON: Power switch pressed- Backup for power switch 1. However, when the power switch is pressed and held, the control functions only when both power switch 1 and 2 are normal.
- Behaves the same way as power switch 1.
Body Electrical > Power Source Control > Data List
Tester Display Start Switch1 Start Switch2 OK
The GTS display changes correctly in response to the power switch operation.
Result
Proceed to OK NG
Result:
OK
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- According to the display on the GTS, read the Data List while wiggling the wire harness.
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - POWER SWITCH)
- Disconnect the H48 certification ECU (smart key ECU assembly) connector.
- Disconnect the H50 power switch connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition H48-23 (SSW1) - H50-5 (SS1) Always Below 1 Ω H48-21 (SSW2) - H50-1 (SS2) Always Below 1 Ω H48-11 (AGND) - H50-6 (AGND) Always Below 1 Ω H48-23 (SSW1) or H50-5 (SS1) - Other terminals and body ground Always 10 kΩ or higher H48-21 (SSW2) or H50-1 (SS2) - Other terminals and body ground Always 10 kΩ or higher H48-11 (AGND) or H50-6 (AGND) - Other terminals and body ground Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 4
- INSPECT POWER SWITCH
Refer to INSPECTION [12/2019 - 11/2023]
Result
Proceed to OK NG Result:
OK
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [12/2019 - 11/2023]
Result:
NG
REPLACE POWER SWITCH. Refer to REMOVAL [12/2019 - 10/2022] , or refer to REMOVAL [10/2022 - 11/2023]