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	Remove ECM cover. Measure voltage at terminal "C51 -1 -24" of ECM connector connected, under the following condition. Engine starter signal specifications While engine cranking: 6 -14 V Is voltage as specified?	Poor "C51-1-24" terminal connection or intermittent trouble. Check for intermittent referring to "INTERMITTENT AND POOR CONNECTION INSPECTION ". If wire and connections are OK, substitute a known-good ECM and recheck	Go to Step 3.
3	Starter signal circuit check Turn OFF ignition switch. Disconnect connectors from ECM. Measure resistance between "C51-1-24" terminal in disconnected ECM connector and "C51-3-6" terminal in disconnected ECM connector. Is resistance less than 100 Ω2?	Substitute a known-good ECM and recheck.	Open in "BLK/YEL" circuit or high resistance in "BLK/YEL" circuit.

Step

Action

Yes

Was "Engine and Emission Control System Check" performed?

Go to Step 2.

Remove ECM cover.
Measure voltage at terminal "C51 -1 -24" of ECM connector connected, under the following condition.

Engine starter signal specifications

While engine cranking: 6 -14 V

Is voltage as specified?

Poor "C51-1-24" terminal connection or intermittent trouble.

Check for intermittent referring to "INTERMITTENT AND POOR CONNECTION INSPECTION ". If wire and connections are OK, substitute a known-good ECM and recheck

Go to Step 3.

Starter signal circuit check

Turn OFF ignition switch.
Disconnect connectors from ECM.
Measure resistance between "C51-1-24" terminal in disconnected ECM connector and "C51-3-6" terminal in disconnected ECM connector.

Is resistance less than 100 Ω2?

Substitute a known-good ECM and recheck.

Open in "BLK/YEL" circuit or high resistance in "BLK/YEL" circuit.