Diagnostic Trouble Codes Troubleshooting

DTC TROUBLESHOOTING

Step	Action	Yes	No
1	Was "Engine and Emission Control System Check" performed?	Go To Step 2.	Go to "ENGINE AND EMISSION CONTROL SYSTEM CHECK :".
2	Check sensor circuit Disconnect connectors from ECM with ignition switch turned OFF. Remove ECM from vehicle body and connect connectors to ECM. Measure voltage between "C45-19" terminal of ECM connector and vehicle body ground with engine running. Is voltage within 0.5 - 4.5 V?	Intermittent trouble. Check for intermittent refer to "INTERMITTENT AND POOR CONNECTION INSPECTION ." If OK, substitute a known-good ECM and recheck.	Go To Step 3.
3	Check sensor circuit for open Disconnect connector from knock sensor with ignition switch turned OFF. Turn ON ignition switch, measure voltage between "RED" wire terminal of knock sensor connector and engine ground. Is voltage 4 - 5 V?	Go To Step 6.	Go To Step 4.
4	Check sensor circuit for open Turn ON ignition switch, measure voltage between "C45-19" terminal of ECM connector and engine ground. Is voltage 4 - 5 V?	Go To Step 5.	Open wire in "RED" circuit.
5	Check sensor circuit for short Disconnect connectors from ECM with ignition switch turned OFF. Measure resistance insulation between "C45-9" terminal of ECM connector and vehicle body ground. Is resistance infinity?	Go To Step 6.	"RED" wire shorted to ground circuit. If wire is OK, substitute a known-good ECM and recheck.
6	Check sensor circuit for short Turn ON ignition switch, measure voltage between "C45-9" terminal of ECM connector and vehicle body ground. Is voltage 0 V?	Go To Step 7.	"RED" wire shorted to other circuits.
7	Check sensor circuit for high resistance Measure resistance between "C45-9" terminal of ECM connector "RED" wire terminal of knock sensor connector. Is resistance below 5 Ω?	Faulty knock sensor.	High resistance wire in "RED" circuit.