Code result
P2AA2
Alternative Fuel Return Line Insufficient Flow
High severity
What it means
The AFCM detects that the flow through the alternative fuel return line is below the expected minimum for the active operating mode. Restricted line, stuck valve, or pump output too low.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Return line restricted by debris
highOne of the most commonly reported causes for this code — check this first.
Return line valve stuck closed
mediumA plausible cause — test and verify before replacing parts.
Related help
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