Volvo Engine D11L (Tier 4) Fault Code: P208A86 PID: PSID 121 FMI: 12 Reductant Pump “A” Control – Signal Invalid

Volvo Engine D11L (Tier 4) Fault Code: P208A86 PID: PSID 121 FMI: 12 Reductant Pump “A” Control – Signal Invalid

CONTROL UNIT:
Engine ECU

FAILURE EVENT:
Malfunctioning of the DEF pump unit detected from ACM. The SCR system is not able to dose DEF.

SYMPTOM:
1. SCR system does not work properly
2. Low power because of engine derate.

CONDITIONS:
None

INHIBITING THE DTC:
None

POSSIBLE CAUSES:
1. Damaged wire harness or connector
2. Defective DEF pump unit pressure sensor.
3. Defective DEF pump.
4. Frozen DEF (heating doesn’t work).
5. Clogged DEF tank breather.
6. Leakage in DEF suction hose.
7. Low DEF tank level.
8. Clogged filter in DEF pump unit.
9. Clogged DEF hose.
10. Clogged DEF tank strainer.