Code result
P0118
Engine Coolant Temperature Circuit High Input
Moderate severity
What it means
The ECT signal voltage is above threshold, which the ECU interprets as an implausibly cold temperature (open-circuit-like behaviour). When this code is active, the ECU runs a default cold-start enrichment that wastes fuel and may cause black smoke.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Open circuit in sensor or wiring
highOne of the most commonly reported causes for this code — check this first.
Corroded sensor connector
mediumA plausible cause — test and verify before replacing parts.
Related help
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