Page 270 - Foton Workshop Manual - Tunland (AT)

04-124 DIAGNOSTICS - ENGINE CONTROL SYSTEM

Failure code Diagnostic items (DTC definition) Trouble location
ECU power output voltage 1 - voltage • Turbocharger actuator and its har-
P1939 is above normal or shorted to low ness
voltage power supply • ECM

• Intake mass flow sensor and its
04
ECU power output voltage 1 - voltage harness
P1941 is below normal or shorted to low • Turbocharger actuator and its har-
voltage power supply ness
• ECM

Ambient air density - data is valid but • Atmospheric pressure sensor and
P1943 above normal operating range - low- its harness
est severity level • ECM

VGT actuator drive temperature is
• Variable geometry turbocharger
too high (calculated value) - data is
P1962 actuator
valid but above normal operating
• ECM
range - lowest severity level
• Postprocessing DPF differential
Postprocessing diesel particulate fil- pressure sensor
P1993
ter (DPF) missing - Condition exists • Postprocessing DPF
• ECM

Sensor power 4 circuit - voltage is
• Accelerator pedal position sensor
P2185 above normal or shorted to low volt-
• ECM and engine harness
age power supply
Sensor power 4 circuit - voltage is
• Accelerator pedal position sensor
P2186 below normal or shorted to low volt-
• ECM and engine harness
age power supply

Variable geometry turbocharger actu- • Variable geometry turbocharger
P2198 ator drive circuit - root cause un- actuator
known • ECM and engine harness

• EGR valve position sensor
• Open circuit in harness, connector
EGR valve position circuit - voltage
or sensor loop
P2271 is above normal or shorted to high • The signal line is short to the sen-
voltage power supply
sor power
• ECM

• EGR valve position sensor
• The signal circuit is open or shorted
EGR valve position circuit - voltage to the ground
P2272 is below normal or shorted to low • Power line is open or shorted to
voltage power supply ground
• Sensor is shorted to the ground
• ECM

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