P0841moderate severityPowertrain
Transmission Fluid Pressure Sensor/Switch A Circuit Range/Performance
on 2005-2011 Audi A6 4.2L V8 · AWD
What this code means
The pressure sensor or switch A signal is out of the expected range compared to commanded pressure. This often points to a sensor drift or hydraulic pressure problem.
Symptoms
- Erratic shifting
- Slipping transmission
- Check engine light on
Common causes
- Faulty pressure sensor
- Low transmission fluid
- Clogged valve body or filter
- Wiring or connector issues
Diagnostic steps
- Retrieve stored codes and freeze frame
- Verify fluid level and quality
- Compare sensor reading to actual line pressure
- Inspect valve body and hydraulic circuit
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