DTC Troubleshooting

NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .

DTC TROUBLESHOOTING CHART

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	Knock sensor circuit voltage check Turn ignition switch OFF position. Disconnect connector from knock sensor. Check for proper terminal connection to knock sensor and ECM connectors If connections are OK, turn ignition switch to ON position. Check that circuit voltage is 5 V between knock sensor signal circuit of knock sensor connector and vehicle body ground. Is it in good condition?	Replace knock sensor.	Go to Step 3.
3	Wire harness check Disconnect connector from ECM with ignition switch turned OFF. Check that knock sensor signal circuit is as follows. Wiring harness resistance of knock sensor signal circuit is less than 3 Ω. Insulation resistance of knock sensor signal circuit is infinity between knock sensor connector and vehicle body ground. Circuit voltage of knock sensor signal circuit is 0 - 1 V with ignition switch turned ON. Are they in good condition?	Substitute a known-good ECM and recheck.	Repair or replace defective wire harness.