Code result
P2186
Engine Coolant Temperature Sensor 2 Circuit Low
Moderate severity
What it means
The second coolant temperature sensor reports a voltage below the lower threshold — typically a short to ground or a sensor with very low resistance.
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
Signal shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Sensor element shorted
mediumA plausible cause — test and verify before replacing parts.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Related help
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