Powertrain
generic / SAE
P2CA4
Particulate Filter Pressure Sensor Signals Swapped A/B
The ECM detects that the particulate filter pressure sensor signals A and B are reversed - low-pressure side reads as high-pressure side and vice versa. Most likely a wiring swap during service.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / numberC / A4
Possible causes
- Sensor connectors A and B swapped during service high
- Sensors installed in wrong positions medium
Symptoms
- Check engine light or DPF warning light on
- Power loss / limp mode
- Increased fuel consumption
- Failed forced regeneration attempts
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 10–100 €
- Estimated time: 0.2–1 h
- Component: pf pressure sensor a
- Component: pf pressure sensor b
- Component: wiring harness
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012