DTC B2274: ACC Monitor Malfunction [10/2018 - ]: Procedure
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- CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY), AUXILIARY BATTERY AND BODY GROUND)
- Disconnect the F44 certification ECU (smart key ECU assembly) connector.
- Disconnect the 4A, 4B and 4F instrument panel junction block assembly connectors.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition F44-16 (ACCD) - 4A-30 Always Below 1 Ω 4B-3 - Body ground Always Below 1 Ω F44-16 (ACCD) or 4A-30 - Other terminals and body ground Always 10 kΩ or higher - Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Switch Condition Specified Condition 4F-1 - Body ground Power switch off 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 2
- CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (ACC RELAY)
- Remove the instrument panel junction block assembly.
Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]
- Connect all of the instrument panel junction block assembly connectors.
- Connect the F44 certification ECU (smart key ECU assembly) connector.
- Measure the voltage according to the value(s) in the table below.
*a Component with harness connected
(Instrument Panel Junction Block Assembly)- - Standard Voltage
Tester Connection Condition Specified Condition 4D-26 - Body ground Power switch on (ACC) 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]
Result:
OK
See step 3
- Remove the instrument panel junction block assembly.
- CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
- Measure the voltage according to the value(s) in the table below.
*a Component with harness connected
(Certification ECU (Smart Key ECU Assembly))Standard Voltage
Tester Connection Condition Specified Condition F44-16 (ACCD) - Body ground Power switch off → Power switch on (ACC) 1 V or less → 8.5 V or higher Result
Proceed to OK NG
Result:
OK
END (TEMPORARY CONNECTION FAILURE IS SUSPECTED). Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ]
Result:
NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]
- Measure the voltage according to the value(s) in the table below.