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Detroit Diesel SPN 3700 FMI 16 indicates that the temperature at the DPF outlet has exceeded the acceptable operating threshold. This code appears on DD13, DD15, and DD16 engines and is a serious fault as excessively high DPF outlet temperatures can damage the filter substrate, surrounding components, and in extreme cases create a fire risk. Immediate attention is required when this code appears.
Symptoms
- Check engine light on
- DPF warning light illuminated
- Active engine derate condition
- Excessive exhaust heat
- Regeneration may be actively occurring or stuck
- Possible smell of burning from exhaust area
- Other DPF temperature or regen codes may appear alongside
Cause
This code triggers when the DPF outlet temperature sensor detects temperatures above the maximum acceptable threshold. Common causes include:
- Uncontrolled or runaway DPF regeneration
- Excessive fuel in the exhaust feeding an uncontrolled regen
- Faulty dosing injector causing over-fueling during regen
- Failed DPF outlet temperature sensor giving false high readings
- Heavily soot loaded DPF igniting during regen
- Engine running rich causing excessive exhaust temperatures
- Faulty regen control system unable to regulate temperatures
Can You Keep Driving?
No. This is a serious fault that can cause permanent DPF damage and poses a potential fire risk. If this code is active stop the vehicle in a safe location away from flammable materials and allow the exhaust system to cool before attempting further diagnosis or operation.
Recommended Action
Stop the vehicle safely and allow the exhaust system to cool completely. Do not attempt a regeneration with this fault active. Have the DPF outlet temperature sensor, dosing injector, and regen control system inspected by a qualified diesel technician. Check the DPF for signs of damage from excessive heat. Do not return the vehicle to service until the root cause has been identified and repaired.
It means the DPF outlet temperature has exceeded the maximum acceptable threshold, indicating a potentially dangerous condition that can damage the DPF and surrounding components.
The most common causes are an uncontrolled or runaway regeneration, a faulty dosing injector causing over fueling during regen, a heavily loaded DPF igniting during regeneration, or a failed outlet temperature sensor.
No. This fault poses a risk of DPF damage and potential fire. Stop the vehicle safely and allow the exhaust system to cool before any further action.
Yes. The ECM will trigger an immediate derate condition to protect the DPF and surrounding components from damage caused by excessive temperatures.
The root cause must be diagnosed and repaired before returning to service. Have the dosing injector, regen control system, and temperature sensor inspected. Do not attempt regeneration until the cause of the high temperature condition has been resolved.
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.