Page 421 - Foton Workshop Manual - Tunland (AT)

DIAGNOSTICS - ENGINE CONTROL SYSTEM 04-275

P1879，P1881，P1921，P1922，P1993，P2639，

P3168-POSTPROCESSING DIESEL PARTICULATE FILTER
DIFFERENTIAL PRESSURE FAULT

P1879-POSTPRECESSING DIESEL PARTICULATE FILTER
DIFFERENTIAL PRESSURE SENSOR CIRCUIT - VOLTAGE IS 04
ABOVE NORMAL OR SHORTED TO HIGH VOLTAGE POWER

SUPPLY
P1881-POSTPRECESSING DIESEL PARTICULATE FILTER

DIFFERENTIAL PRESSURE SENSOR CIRCUIT - VOLTAGE IS
BELOW NORMAL OR SHORTED TO LOW VOLTAGE POWER
SUPPLY

P1921-POSTPROCESSING DIESEL PARTICULATE FILTER
DIFFERENTIAL PRESSURE - DATA IS VALID BUT ABOVE

NORMAL OPERATING RANGE - MEDIUM SEVERITY LEVEL
P1922-POSTPROCESSING DIESEL PARTICULATE FILTER
DIFFERENTIAL PRESSURE - DATA IS VALID BUT ABOVE

NORMAL OPERATING RANGE - HIGHEST SEVERITY LEVEL
P1993-POSTPRECESSING DIESEL PARTICULATE FILTER (DPF)

MISSING - CONDITION EXISTS
P2639-POSTPROCESSING DIESEL PARTICULATE FILTER
DIFFERENTIAL PRESSURE - DATA IS VALID BUT ABOVE

NORMAL OPERATING RANGE - LOWEST SEVERITY LEVEL
P3168-POSTPROCESSING DIESEL PARTICULATE FILTER

SYSTEM - DATA IS VALID BUT ABOVE NORMAL OPERATING
RANGE - MEDIUM SEVERITY LEVEL

Description
1 . The engine control module (ECM) provides a 5V power source to the
postprocessing DPF differential pressure sensor through the sensor power
circuit.The ECM also provides a grounding to the sensor circuit. Postprocessing
DPF pressure differential sensor on the postprocessing DPF differential pressure
sensor signal circuit provides a signal to the ECM.The signal voltage of this
sensor varies according to the differential pressure at the two ends of the
postprocessing DPF.

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