P0847
PowertrainTransmission Pressuremoderate severityTransmission Fluid Pressure Sensor/Switch B Circuit Low
What P0847 Means
The PCM detects a voltage lower than expected from transmission fluid pressure sensor/switch B. This can affect shift timing and transmission control.
Symptoms
- Harsh or erratic shifting
- Transmission warning light on
- Possible limp mode
Common Causes
- Faulty fluid pressure sensor B
- Low transmission fluid
- Wiring short to ground
- Faulty PCM/TCM
Diagnostic Steps
- Scan and record freeze frame data
- Check transmission fluid level and condition
- Inspect sensor B wiring and connector
- Measure sensor voltage and compare to spec
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✓ Autel official store
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