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BMW 335d 480A 481A Fault Codes

BMW 335d 480A & 481A Fault Codes

mean that your Diesel Particulate Filter (DPF) is Heavily contaminated

When the diesel particulate filter (DPF) is overloaded regeneration is prevented by the Engine Control Unit (DDE). You may find that the BMW 480A or 481A codes can be cleared using a scan tool but return immediately after your start the engine or after a short drive cycle. 

Let’s take a look at both codes in more detail;
480A Diesel Particulate Filter is Heavily contaminated ( exhaust back pressure is too high)

481A Diesel Particulate Filter is Heavily contaminated ( exhaust back pressure is above the maximum permissible values)

Many garages will be tempted to clean the DPF on the vehicle using chemicals this does not fix the vehicle and is only a temporary solution.

To rectify this fault you must establish the cause of the contamination. Cleaning the DPF will result in the code returning in the near future.

Do not clean the DPF until you have identified and rectified the cause.

What are the common causes of this code?

  • Out of date software
  • Driving Profile
  • Other Engine Faults Present

Tests & Checks for BMW 480A or 481A

  • Check software version
  • Check Driving Profile
  • Retrieve Fault Codes from all modules
    • Check Intake System for leaks
    • Check operation of exhaust temperature sensors
    • Air & Coolant Temperature sensors
    • Exhaust Pressure sensor (check pressure at idle, 2000 rpm & Wide-open throttle)
    • Check distance since the last successful regeneration
    • Request service regeneration in service mode, and carry out the regeneration drive cycle.
      • The regeneration drive cycle 45 mins at a constant speed, with all electrical consumers switched on. Monitor exhaust gas temperatures, aim for 280-350℃ which should allow passive regeneration to take place. If successful the exhaust pressure will drop to within permissible levels. Allowing regeneration to take place (exhaust temperatures will increase to 600-700℃ ).
  • After the Test Drive
    • Check distance since the last successful regeneration, this will confirm the test drive was successful or not.
      Test Exhaust back pressure it should now be within specification.

What if the Regeneration was not successful and BMW code 480A has returned?

  • There is still a fault that requires rectification
    • Check the Intake System for leaks
    • Test the Air mass meter
    • Check the swirl flaps for correct operation
    • Check the exhaust gas recirculation system
    • Test the glow plugs and module for correct operation
    • Check thermostat (DPF requires min temperature of 75℃)
    • Check exhaust pressure sensor for correct operation
    • Check exhaust pressure sensor pipes for blockages/splits
    • Check the plausibility and operation of the exhaust temperature sensors

BMW 480A & 481A Warning

Do not clean the DPF until you have established and repaired the cause.

Very happy with the work I had done the staff are absolutely fantastic and will definitely be using them again would highly recommend them to everyone.
David Foyle
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