DD-654-5 moderate Detroit Diesel DD Series ›

Injector Cylinder #4 Current Below Normal

The DD-654-5 (Detroit Diesel DD Series) diesel fault code means: Injector Cylinder #4 Current Below Normal. This is a moderate severity code.

This is a standard J1939 fault, not a proprietary code. DD-654-5 is how this equipment displays SPN 654 with FMI 5 (current below normal or open circuit) 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.

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Keep driving?
Yes, with caution
DIY difficulty
advanced
Estimated cost
$500-$2,200
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What Are the Symptoms of DD-654-5?

  • Check Engine Light / Amber Warning Lamp illuminated
  • Rough idle or misfire
  • Noticeable power loss under load
  • Black or white smoke from exhaust

What Causes DD-654-5? (Most Likely First)

  • Failed injector Likely
  • Harness fault Likely

Can I Still Drive with DD-654-5?

Yes, with caution. DD-654-5 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is Detroit Diesel fault code DD-654-5?

Detroit Diesel fault DD-654-5 (SPN 654 FMI 5) indicates: Injector Cylinder #4 Current Below Normal. It is a moderate-severity fault and is commonly seen on DD13/DD15/DD16 engines in Freightliner and Western Star chassis.

Can I drive my Freightliner or Western Star with fault DD-654-5?

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-654-5?

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-654-5?

  1. Cylinder cutout via DDDL to isolate #4.

  2. Inspect harness.

  3. Replace injector.

Sources 2

This page is built from documented references. Verify against your own service info before repair work.

Which Vehicles Commonly Get DD-654-5?

  • 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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More Detroit Diesel DD Series codes → Diesel home All diesel codes Heavy-duty Guides

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