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Detroit Diesel SPN 3713 FMI 18 indicates that the Diesel Particulate Filter soot load has reached a critical level requiring immediate attention. This is a more severe version of the FMI 16 fault and appears on DD13, DD15, and DD16 engines when soot accumulation has exceeded the point where normal regeneration may be sufficient. Immediate action is required to avoid severe derate or DPF damage.
Symptoms
- Check engine light on
- DPF warning light illuminated
- Active derate condition
- Significantly reduced engine power
- Vehicle speed may be limited
- Parked regen may be blocked or unable to complete
- Exhaust back pressure significantly elevated
Cause
This code triggers when soot load in the DPF has reached the critical threshold, typically after the FMI 16 warning was not addressed. Common causes include:
- FMI 16 fault left unresolved allowing soot to continue accumulating
- Multiple failed regeneration attempts
- Regen inhibit switch preventing regeneration cycles
- Severely clogged DPF beyond normal regen capability
- Engine fueling or combustion issues causing excessive soot output
- Faulty DPF differential pressure sensor
- Operating conditions preventing regeneration temperatures from being reached
Can You Keep Driving?
This is a severe fault and the engine will be in an active derate condition. Continued operation risks permanent DPF damage and potential engine damage from excessive exhaust back pressure. A parked regeneration should be attempted immediately and if unsuccessful the vehicle should be taken to a qualified diesel technician.
Recommended Action
Attempt a parked regeneration immediately if conditions allow. If the parked regen fails or cannot initiate, the vehicle needs professional service. At this soot level a forced regeneration using diagnostic software may be required. In severe cases the DPF may need to be removed for professional cleaning or replacement.
It means the DPF soot load has reached a critical level that requires immediate action. This is more severe than the FMI 16 warning and indicates the regeneration process has not kept up with soot accumulation.
Most commonly this fault develops when the FMI 16 warning was not addressed in time. Other causes include failed regeneration attempts, a severely clogged DPF, or engine issues causing excessive soot production.
Not recommended. The engine is in active derate and continued operation risks permanent DPF damage and increased exhaust back pressure that can harm the engine.
Yes. This is a severe derate triggering fault and power and speed will be significantly restricted until the soot load is reduced.
Attempt a parked regeneration immediately. If unsuccessful seek professional service for a forced regen using diagnostic software. If the DPF is too severely clogged it may require removal for cleaning or replacement before the code will clear.
Related codes
Need Immediate Help With This Fault Code?
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Important Notice
The information provided above is for general informational purposes only and should not replace official OEM service procedures. Always consult the manufacturer’s service manual or a qualified diesel technician before performing repairs. Operating a vehicle with active fault codes may result in further damage.