Code result
P2638
Torque Management Feedback Signal A Range/Performance
Moderate severity
What it means
The torque feedback signal A is present but its value is implausible against measured engine load and speed. Sender calibration or sensor offset is suspected.
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
Sender calibration drift
mediumA plausible cause — test and verify before replacing parts.
Bus value corrupted by EMI
mediumA plausible cause — test and verify before replacing parts.
Sensor element aged beyond calibration window
lowLess common, but worth ruling out after the more likely causes.
Related help
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