Fuel Rail Pressure Relief Valve Open
The DD-5571-0 (Detroit Diesel DD Series) diesel fault code means: Fuel Rail Pressure Relief Valve Open. This is a moderate severity code.
Unverified. We could not confirm this code's definition against freely available manufacturer documentation, so treat the meaning, severity and fix guidance on this page as unconfirmed. Check it against the manufacturer's service information for your exact model and serial range before acting on it. This page is kept out of search engines for that reason, and we are working through this family manual by manual.
This is a standard J1939 fault, not a proprietary code. DD-5571-0 is how this equipment displays SPN 5571 with FMI 0 (data valid but above normal — most severe) under the SAE J1939 standard used across heavy equipment. The same SPN can appear on any J1939-compliant machine regardless of brand — so cross-referencing it against your engine maker's documentation is valid even when the equipment brand differs.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- advanced
- Estimated cost
- $500-$2,200
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View pilot availability →What Are the Symptoms of DD-5571-0?
- Check Engine Light / Amber Warning Lamp illuminated
- Noticeable power loss under load
- Hard starting or extended crank
What Causes DD-5571-0? (Most Likely First)
- Rail pressure rose high enough to force the relief valve open (fuel pressure control or metering fault) Likely
- Relief valve leaking or stuck open Possible
- Rail pressure sensor reading incorrectly Possible
Can I Still Drive with DD-5571-0?
Yes, but fix soon. DD-5571-0 is rated moderate severity. It is not an immediate stop-driving fault, but it will not clear itself — book the repair rather than ignoring it.
Frequently Asked Questions
What is Detroit Diesel fault code DD-5571-0?
Detroit Diesel fault DD-5571-0 is SPN 5571 with FMI 0. SPN 5571 is the common-rail fuel pressure relief valve; an engine-maker table for the same SPN-FMI pair (Deutz TCD 2.2) reads "Open rail fuel pressure relief valve was detected." An earlier version of this page called it a pressure regulator flow-demand fault. Detroit's own definition was not available to us, so treat this meaning as unconfirmed for Detroit engines.
Can I drive my Freightliner or Western Star with fault DD-5571-0?
It depends on severity. Critical and serious faults trigger derate or engine shutdown — do not continue driving. Moderate faults usually allow continued operation short-term but schedule repair to prevent cascading aftertreatment damage.
How much does it cost to fix Detroit Diesel fault DD-5571-0?
Estimated repair cost is $500-$2,200. Sensor/harness fixes fall at the low end; turbo actuator, injector, aftertreatment component, or head gasket repairs fall at the high end. Detroit DDDL software and sometimes factory parameter reset are required for proper reset.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose DD-5571-0?
Read rail pressure, commanded rail pressure and any companion fuel-system codes with Detroit diagnostic software.
Look for a fuel metering or pressure control fault that would drive rail pressure above its limit.
Check the relief valve and its return line for continuous flow, and replace the valve only once pressure control is confirmed good.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
Which Vehicles Commonly Get DD-5571-0?
- Freightliner Cascadia with DD15
- Freightliner Cascadia with DD13
- Freightliner Cascadia with DD16
- Western Star 4700 with DD13/DD15
- Western Star 4900 with DD15/DD16
- Western Star 5700 XE with DD15
- Freightliner M2 106 with DD13
- Freightliner M2 112 with DD13
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