P2518
A/C Refrigerant Pressure Sensor B Circuit High
What it means
A/C refrigerant pressure sensor B signal voltage reads above the upper limit. Typically a short to reference voltage in the signal line, an open signal return, or an overpressure event briefly pegging the sensor. ECM disables variable compressor control to protect the system.
Is it safe to drive?
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 wire shorted to reference voltage
highOne of the most commonly reported causes for this code — check this first.
Open signal return at the sensor
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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