Injector Cylinder #1 Current Above Normal
The DD-651-6 (Detroit Diesel DD Series) diesel fault code means: Injector Cylinder #1 Current Above Normal. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- advanced
- Estimated cost
- $500-$2,200
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Common Symptoms
- Check Engine Light / Amber Warning Lamp illuminated
- Rough idle or misfire
Probable Causes (Ranked by Likelihood)
- Shorted injector solenoid Likely
- Harness short to ground Likely
Step-by-Step Diagnostic Procedure
Coil resistance test — shorted reads <0.3 ohm.
Harness short-to-ground ohm test.
Replace injector.
Frequently Asked Questions
What is Detroit Diesel fault code DD-651-6?
Detroit Diesel fault DD-651-6 (SPN 651 FMI 6) indicates: Injector Cylinder #1 Current Above 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-651-6?
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-651-6?
Typical 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.
Sources
This page is built from documented references. Verify against your own service info before repair work.