P0871
PowertrainTransmission Pressuremoderate severityTransmission Fluid Pressure Sensor/Switch C Circuit Range/Performance
What P0871 Means
The transmission fluid pressure sensor or switch C circuit is reading outside its expected range. This can cause incorrect shift timing and pressure control issues.
Symptoms
- Harsh or delayed shifts
- Transmission slipping
- Check engine light on
Common Causes
- Faulty transmission fluid pressure sensor
- Low or dirty transmission fluid
- Wiring or connector problems
- Internal valve body fault
Diagnostic Steps
- Check transmission fluid level and condition
- Scan for related transmission codes
- Inspect sensor wiring and connector
- Test sensor signal against actual pressure
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