Ignition Circuit [06/2018 - ]: Procedure
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- CHECK TERMINAL VOLTAGE (POWER SOURCE OF IGNITION COIL ASSEMBLY)
*a Front view of wire harness connector
(to Ignition Coil Assembly)- Disconnect the ignition coil assembly connectors.
- Turn the power switch on (IG).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition C45-1 (+B) - C45-3 (GND) Power switch on (IG) 11 to 14 V C46-1 (+B) - C46-3 (GND) Power switch on (IG) 11 to 14 V C47-1 (+B) - C47-3 (GND) Power switch on (IG) 11 to 14 V C48-1 (+B) - C48-3 (GND) Power switch on (IG) 11 to 14 V Result
Proceed to OK NG
Result:
NG
See step 3
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (IGNITION COIL ASSEMBLY - ECM)
- Disconnect the ignition coil assembly connectors.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition C45-2 (IGT1) - C88-49 (IGT1) Always Below 1 Ω C46-2 (IGT2) - C88-48 (IGT2) Always Below 1 Ω C47-2 (IGT3) - C88-47 (IGT3) Always Below 1 Ω C48-2 (IGT4) - C88-46 (IGT4) Always Below 1 Ω C45-2 (IGT1) or C88-49 (IGT1) - Body ground and other terminals Always 10 kΩ or higher C46-2 (IGT2) or C88-48 (IGT2) - Body ground and other terminals Always 10 kΩ or higher C47-2 (IGT3) or C88-47 (IGT3) - Body ground and other terminals Always 10 kΩ or higher C48-2 (IGT4) or C88-46 (IGT4) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE ECM. Refer to REMOVAL [06/2018 - 08/2020] , or refer to REMOVAL [08/2020 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- CHECK HARNESS AND CONNECTOR (IGNITION COIL ASSEMBLY - BODY GROUND)
- Disconnect the ignition coil assembly connectors.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition C45-3 (GND) - Body ground Always Below 1 Ω C46-3 (GND) - Body ground Always Below 1 Ω C47-3 (GND) - Body ground Always Below 1 Ω C48-3 (GND) - Body ground Always Below 1 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 4
- CHECK HARNESS AND CONNECTOR (IG2 NO. 1 RELAY - IGNITION COIL ASSEMBLY)
- Disconnect the IG2 NO. 1 relay from No. 1 engine room relay block and No. 1 junction block assembly.
- Disconnect the ignition coil assembly connectors.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition 3 (IG2 NO. 1 relay) - C45-1 (+B) Always Below 1 Ω 3 (IG2 NO. 1 relay) - C46-1 (+B) Always Below 1 Ω 3 (IG2 NO. 1 relay) - C47-1 (+B) Always Below 1 Ω 3 (IG2 NO. 1 relay) - C48-1 (+B) Always Below 1 Ω 3 (IG2 NO. 1 relay) or C45-1 (+B) - Body ground and other terminals Always 10 kΩ or higher 3 (IG2 NO. 1 relay) or C46-1 (+B) - Body ground and other terminals Always 10 kΩ or higher 3 (IG2 NO. 1 relay) or C47-1 (+B) - Body ground and other terminals Always 10 kΩ or higher 3 (IG2 NO. 1 relay) or C48-1 (+B) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
GO TO ECM POWER SOURCE CIRCUIT. Refer to ECM Power Source Circuit [06/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR