Code result
P0939
Hydraulic Pump Relay Control Circuit High
Moderate severity
What it means
The hydraulic oil temperature sensor reports a circuit low fault. Oil temperature feedback for hydraulic system is unreliable.
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
Temperature sensor failed
highOne of the most commonly reported causes for this code — check this first.
Wiring fault
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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