Technical note: diesel additive on PSA (SID, DCM & EDC)

Technical Note : Diesel Additivation on PSA (SID, DCM & EDC)

The "Phantom Fault" Phenomenon

After a software removal of the DPF (DPF OFF), it is common to see messages such as "Diesel additive level too low" or "Risk of DPF clogging".

The reason : The engine ECU (SID807, DCM3.5, etc.) no longer manages the DPF, but the BSI (and sometimes a separate additivation module) continues to count cerine injections based on fuel fill-ups. If the counter reaches its limit or the pump is burnt out, the BSI forces the "SERVICE" light to turn on even if the engine runs perfectly.

Specificities by ECU Family

Total Neutralization Procedure (Diagbox / Launch)

For a "clean" result without any customer comeback, the engine mapping modification must be accompanied by these configuration steps :

1. BSI Telecoding (Essential)

• Menu : Configuration / Customer Personalization.
• Action : Set the "Particulate filter presence" option to ABSENT or NO.
• Why ? This tells the BSI that it should no longer send DPF/Additive alert requests to the instrument cluster.

2. Deactivation of the Additivation ECU

On vehicles with a separate module (e.g., SID803) or multiplexed pump (e.g., DCM3.5/EDC17C60) :

• Menu : Global Configuration > List of present ECUs.
• Action : Declare the "Diesel additivation ECU" as ABSENT.

3. Preventive "Reset"

Pro Tip : If you still have "Minimum level reached" faults after telecoding, temporarily set the DPF back to "Present", go to the additive maintenance menu, perform a "Tank/additive bag replacement" (counter reset), then set everything back to "Absent".

Case of a failing Additive Pump

If the additive pump is electronically burnt out, it can generate communication errors on the CAN network, causing the car to "beep" even if the DPF is OFF.

Solution : After completing the telecoding above, physically disconnect the additive pump connector (located under the chassis, at the cerine tank level). Since the BSI is no longer looking for it (declared absent), the physical absence will not create a fault.

End-of-job checklist

• Fault reading (Global) : No DPF/Additive fault in the BSI.
• Instrument cluster : No "Service" light or warning message at start-up.
• Fuel flap : Check that opening the flap no longer triggers anything in the BSI live data.