4A4-6
UnclassifiedLubrication
What This Code Means
Electric failure in the fuel metering unit (MeUn) power stage at Low Side; Electric failures in the control lamp for Glow Plug activation; Actual boost pressure is higher than target boost pressure beside a defined threshold; Underboost; Positive boost pressure deviation; Electric failure in the power stage of Bitron actuator; Electric failure in the power stage of VGT actuator; Turbine upstream pressure Signal Range Errors; No response from power stage controller; Erroneous response detected by the ECM processor
Possible Causes
- •Fuel metering unit to common rail (MeUn) hardware detected electrical failure (voltage or current deviation)
- •Power stage for the control lamp for Glow Plug activation hardware detected electrical failure
- •Boost pressure value monitoring failure
- •Deviation of actual boost pressure from target pressure while the engine is running within the specified working area
- •Power stage of Bitron actuator hardware detected electrical failure
- •Power stage of VGT or Bitron actuator hardware detected electrical failure
- •Out of range raw voltage signal (Exh_uRawPTrbnUs) acquired via hardware connected turbine upstream pressure sensor
- •SPI bus communication failure between ECM processor and power stage controller
Related Winco Fault Codes
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