Detroit DD16 EPA10 (2010-13) Fault Code: SPN 4334 FMI 7 (ACM) DEF Pressure Low

NOTE: This code sets when the aftertreatment control module (ACM) detects that the diesel exhaust fluid (DEF) pump is not building 72 psi during a pressure build cycle (60 seconds).

DESCRIPTION:
DEF pressure low.

MONITORED PARAMETER:
DEF pressure

TYPICAL ENABLING CONDITIONS:
1. Pressure limiting unit on.
2. Dosing enabled.

MONITOR SEQUENCE:
None

EXECUTION FREQUENCY:
Continuous when enabling conditions met.

TYPICAL DURATION:
60 seconds

DASH LAMPS:
1. MIL
2. CEL

ENGINE REACTION:
Derate 25%

VERIFICATION:
SCR quantity test.

NOTE: If there is oil present in the air system, the pressure limiting unit (PLU, diesel exhaust fluid (DEF) metering unit and the associated air lines should be cleaned to prevent repeat failures.

NOTE: If any active codes for Pressure Limiting Valve (PLU), DEF pump, DEF pressure sensor, DEF air pressure, or DEF tank level/zone faults, fix those first

PROBABLE CAUSES:
1. Contaminated DEF fluid.
2. Low vehicle air pressure (Under 100 PSI).
3. Air feed liens to DEF pump are leaking.
4. DEF pressure sensor.
5. DEF pressure sensor connector/harness.
6. DEF pump switching valve.
7. DEF pump failure.