System: Powertrain (P-Code)
SAE Standard (Generic)
Family: Diesel Fuel Presence Sensor Circuit
Code P2AAF: Diesel Fuel Presence Sensor Circuit High
Diagnostic & Technical Explanation
Code P2AAF (Diesel Fuel Presence Sensor Circuit High) covers the sensor that detects whether diesel fuel (rather than air or gasoline) is present in the injection system, used on dual-fuel and fuel-quality-sensitive platforms to prevent running the engine on the wrong fuel. The ECM flags an open, shorted, or implausible signal. Causes are a fouled sensor element from fuel contamination, a corroded connector, or damaged wiring between the sensor and ECM.
First-listed procedure
Rank #1
Inspect fuel presence sensor connector
Easy DIY
This is the first procedure in the authored
consideration order, not a measured cause likelihood. Execute it only when its prerequisites
and diagnostic findings support it. Its cost and labor estimates (where known), the step-by-step procedure and the
remaining 2 procedure(s) are in the licensed dataset. Ordering context.
Full family: Diesel Fuel Presence Sensor Circuit
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)