DESCRIPTION:Diesel Exhaust Fluid (DEF) pressure relief valve stuck closed.
MONITORED PARAMETER:DEF Pressure
TYPICAL ENABLING CONDITIONS:When service routine is enabled and during in-use checks under non-dEF dosing conditions.
MONITOR SEQUENCE:None
EXECUTION FREQUENCY:Service tool and during in-use checks under non-DEF dosing conditions.
TYPICAL DURATION:2 Seconds
DASH LAMPS:None
ENGINE REACTION:None
VERIFICATION:SCR ADS self-check.
NOTE: If any other codes are active, fix those first.
PROBABLE CAUSES:1. Inspect the DEF dosing unit and DEF pump harness wiring & connectors.2. Check all DEF lines for damage/blocks/kinks.3. DEF pump suction filter.4. DEF dosing unit inlet filter.5. DEF tank header.6. DEF tank supply filter.7. Replace the pressure relief valve.