What this code means

The PCM detected intermittent high voltage on the Engine Coolant Temperature sensor circuit, indicating the sensor is sporadically reporting very low temperatures.

Symptoms

• Check Engine Light
• Rich running condition
• Poor fuel economy
• Cooling fans not activating when needed

Common causes

• Intermittent open in ECT circuit
• Loose ECT connector
• Faulty ECT sensor
• Corroded terminals

Diagnostic steps

1. Monitor ECT readings for erratic spikes
2. Wiggle test ECT connector
3. Test sensor resistance across temperature range
4. Check connector terminals

Repair notes

Clean and secure ECT connector. Replace sensor if faulty.

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