DDEC III/IV Single ECM Troubleshooting

Section 48.1 Description of Flash Code 48

Section 48.1
Description of Flash Code 48

Flash Code 48 indicates that the ECM has detected that the Fuel Pressure has dropped below a programmed limit. This condition is normally associated with a restriction in the fuel supply system:‪

  • Plugged fuel filter
  • Low fuel supply

Note: Not all engines use a fuel pressure sensor, see Figure "Fuel Pressure Sensor" .

For gas engines, code 48 indicates that the air inlet pressure has dropped below a calibration limit.‪

Flash Code 48 is also used to identify the EGR Delta-Pressure, or EGR temperature is below programmed limits. This condition is typically due to:‪

  • EGR valve not opening completely
  • EGR valve not opening at all – leaking CAC.
  • Leaking EGR piping/hoses.

Flash Code 48 also indicates the exhaust gas temperature fell below calibrated limits, or EGR Delta-Pressure fell below calibrated limits. Possible causes include: ‪

  • EGR valve not opening
  • EGR valve not opening fully
  • Leaking CAC

Flash Code 48 also indicates the TCI (Turbo Compressor Inlet) or TCO (Turbo Compressor Outlet) temperature fell below the calibrated limits. Possible causes include: ‪

  • Leaking CAC
  • Leaking inlet piping
  • EGR valve not opening properly


DDEC III/IV Single ECM Troubleshooting Guide - 6SE497
Generated on 10-13-2008

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