Note. If DTC P0117 and/or P0118 are stored at the same time as DTC P0116, troubleshoot those DTCs first, then recheck for DTC P0116.
- Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Check the ECT with the scan tool or the HDS. Is 176-212°F (80-100°C) or 0.5-0.8 V indicated? YES -Intermittent failure, system is OK at this time. Check the thermostat and the cooling system. NO -Check the thermostat and the cooling system. If they are OK, replace the ECT sensor.