Diagnosis & Repair (Using OBD-II Scan Tool)
- Remove the engine room ECM cover and hood. Turn the ignition switch ON. Measure the voltage between terminal STA of the ECM connector and body ground while cranking engine. See Fig 1. Voltage should be 6 volts or more. If not, go to next step.
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- Check park/neutral position switch. See DTC P0705: TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT) . Replace park/neutral position switch as necessary. If okay, go to next step.
- Turn the ignition switch ON. Measure the voltage between terminal STA of the ECM connector and body ground while cranking engine. See Fig 1. Voltage should be 6 volts or more. If not, go to next step.
- Check continuity between the connector terminals on ignition switch. See IGNITION SWITCH CONNECTOR RESISTANCE table. If okay, go to next step. If not okay, replace ignition switch and go to next step.
- Check for open in harness and connector between ECM and starter relay. Repair as necessary. If okay, go to next step.
- Turn the ignition switch ON. Measure the voltage between terminal STA of the ECM connector and body ground while cranking engine. See Fig 1. If voltage is 6 volts or more, system is okay. If not, check and replace ECM.