Code result
P2CA4
Particulate Filter Pressure Sensor Signals Swapped A/B
Moderate severity
What it means
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.
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
Sensor connectors A and B swapped during service
highOne of the most commonly reported causes for this code — check this first.
Sensors installed in wrong positions
mediumA plausible cause — test and verify before replacing parts.
Related help
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