DESCRIPTION:This diagnostic is typically an under pressurized diesel exhaust fluid (DEF) system.
MONITORED PARAMETER:DEF pump speed vs. DEF pressure.
TYPICAL ENABLING CONDITIONS:DEF pump enalbed or on-off-cycle request.
EXECUTION FREQUENCY:Continuous when enabling conditions met.
TYPICAL DURATION:Continuous until resolved.
DASH LAMPS:None
ENGINE REACTION:None
VERIFICATION:Parked regeneration/Selective catalyst reduction SCR ADS self-check routine.
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.