Detroit DD13 SPN 3055 FMI 14 — DPF Condition (Parked Regeneration Required)

Code Details

Plain-English Meaning

The Detroit DD13 aftertreatment system regenerates the DPF in two ways: passively during highway operation when exhaust temperatures are naturally high enough, and actively by commanding the hydrocarbon doser to raise exhaust temperatures to the soot-oxidation range during driving. When neither passive nor active driving regen can maintain soot levels below the warning threshold — usually because the duty cycle involves too much low-speed or idle operation — the ACM requests a parked regen. A parked regen runs the DD13 at elevated idle with the vehicle stationary, using the full output of the HC doser to raise DPF temperatures and burn off accumulated soot while there is no forward motion to interrupt the cycle. SPN 3055 FMI 14 is the formal notification from the aftertreatment system that this parked regen is now required to restore normal DPF function. The vehicle remains operable after this fault sets, but a speed or power derate may be applied if the parked regen is not initiated promptly.

SPN 3055 is Aftertreatment 1 Diesel Particulate Filter Condition; FMI 14 is a condition-exists flag indicating the DPF soot load has reached the threshold level that requires a forced active regen in stationary mode. On GHG17 Detroit DD13 engines, the ACM monitors DPF soot load by measuring exhaust differential pressure across the filter using a delta pressure sensor. When the calculated soot load reaches the parked regen request threshold, the ACM sets SPN 3055 FMI 14 and activates the driver warning. Detroit DiagnosticLink can display the current DPF soot load percentage and the regen inhibit history to determine how many driving regens have been interrupted or blocked. A parked regen can be commanded directly through DiagnosticLink for service and diagnostic purposes, and DiagnosticLink can monitor the regen cycle progress to confirm the soot load drops during the procedure.

Common Symptoms

• DPF regeneration required indicator lamp illuminated on the instrument cluster
• Driver display showing a parked regen required message
• Possible engine power or speed limitation if the parked regen request has been ignored for an extended period
• Reduced performance in stop-and-go or urban driving conditions where passive regen is limited

Possible Causes

Possible causes may include the items below. The list is not a parts diagnosis.

• Extended low-speed, stop-and-go, or urban duty cycle preventing driving regen from completing
• Repeated driver inhibition or interruption of driving regen requests
• Short-trip operation where the engine does not reach temperatures sufficient for passive or active regen
• Frequent driving regen interruptions due to traffic, grade, or load conditions
• DPF differential pressure sensor fault producing an incorrect soot load reading

First Checks

• Follow the driver display instructions to perform a parked regen in a safe outdoor location with the vehicle stationary and the parking brake engaged
• Ensure the regen area is free of flammable materials near the exhaust outlet, which will produce elevated heat during the regen cycle
• Connect Detroit DiagnosticLink to monitor DPF soot load before and after the parked regen to confirm the cycle completed successfully and soot load dropped
• If the parked regen fails to complete or the DPF soot load does not drop, inspect the HC doser and DPF differential pressure sensor for faults that may be preventing successful regen
• Review the regen history in DiagnosticLink to determine how many driving regen attempts were made and how many completed before the parked regen was required

Can I Keep Driving?

The truck is driveable when SPN 3055 FMI 14 first sets, but performance may be reduced. Complete the parked regen as soon as safely possible to avoid escalation to a more severe derate as soot load continues to increase.

Related Lookup Pages

• FMI 14 explanation
• Detroit Diesel manufacturer hub
• Aftertreatment fault codes
• Search this code