P0118
Engine Coolant Temperature Sensor Circuit 1 High Input
Description
Engine Coolant Temperature Sensor Circuit 1 High Input This body system diagnostic trouble code indicates an issue with the vehicle's comfort, safety, or convenience systems.
OBD Codes Details
Possible Causes
Blown fuse, faulty switch, damaged wiring harness, poor electrical connection
Solution
Check fuses and relays, inspect wiring harness, test switches and sensors, repair damaged circuits
Symptoms
- Check engine light illuminated
- Cooling fans may not activate when needed
- Engine running lean, potential overheating
- Inaccurate or stuck temperature gauge reading
- Poor fuel economy
Diagnostic Recommendations
- Inspect ECT sensor wiring for an open circuit
- Check ECT sensor connector for damage or poor contact
- Test ECT sensor resistance at known coolant temperatures
- Verify coolant level is adequate
- Replace ECT sensor if it reads open circuit
Repair Cost Estimate
- ECT sensor replacement: $20-100
- Wiring repair: $80-200
- Coolant top-off: $30-80
- Diagnostic scan: $80-150
- Total diagnostic and repair: $100-400
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Fact-checking completed
Verified by:
Pavel Volkov
Created:
Last updated:
Information verified against official sources
Official Sources
Society of Automotive Engineers
Official OBD-II diagnostic trouble codes standard (SAE J2012)
Automotive engineering standards organization
International Organization for Standardization
International standard for vehicle diagnostic systems
International standards for automotive diagnostics
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