DTC 22 - Engine Coolant Temperature Sensor Signal

The engine coolant temperature sensor is a thermistor that changes its resistance value according to engine coolant temperature. ECM supplies a 5-volt reference voltage to engine coolant temperature through ECM terminal "E12". When sensor resistance changes, ECM changes fuel injection volume to improve driveability during cold engine operation.

A failure code is set when there is an open or short in engine coolant temperature sensor circuit for .5 second or more. Check for open or short in engine coolant temperature sensor circuit, a faulty sensor or ECM.

Fig 1: DTC 22 - Schematic

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Fig 2: DTC 22 - Voltage Reference Chart

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Fig 3: DTC 22 - Diagnostic Flowchart (1 Of 2)

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Fig 4: DTC 22 - Diagnostic Flowchart (2 Of 2)

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