The Motorcraft 4C3Z-9D930-AA Fuel Injection Control Module (FICM) Wiring Harness is a genuine Ford OEM replacement engine sub-harness engineered specifically for mid-production 2004 Ford Super Duty trucks and Excursions equipped with the 6.0L Powerstroke diesel engine. Responsible for transmitting critical 48-volt open and close pulses between the FICM and the fuel injectors, this factory-original harness incorporates OEM heat-shielded conduit, heavy-gauge copper conductors, factory-molded locking connector plugs, and integrated sensor leads calibrated for vehicles manufactured between December 2, 2003, and April 10, 2004.

Quick Specs & Kit Inclusions

• Application: Engine-mounted Fuel Injection Control Module (FICM) to fuel injector wiring sub-harness
• Production Build Window: Specifically fits vehicles built from 12/02/2003 through 04/10/2004
• Voltage Integrity: High-current 48V DC transmission rating with low internal resistance to protect FICM power supply boards
• Integrated Terminations: Features 8 dedicated fuel injector plugs with mechanical retention clips, primary FICM module interface connectors, Exhaust Backpressure (EBP)/engine sensor leads, and factory eyelet grounds
• Manufacturing Standard: Genuine Ford Motorcraft Original Equipment Manufacturer (OEM) component
• Emissions Status: 50-state legal (direct OE replacement electrical assembly)
• Direct Interchange Part Numbers: Ford 4C3Z-9D930-AA, Motorcraft 4C3Z9D930AA
• What's in the Box: (1) Genuine Ford Motorcraft 4C3Z-9D930-AA Complete Injector Wiring Harness Assembly

Problem Solved: Curing Broken Connector Clips, Misfires & 48V Voltage Drops

Underhood conditions on the 6.0L Powerstroke subject the FICM harness to continuous vibration and extreme radiant heat from the turbocharger and exhaust manifolds. Over time, original wire insulation embrittles, leading to chafing, internal wire fractures, or high-resistance opens that drop FICM output voltage below safe operating thresholds. More commonly, the plastic locking tabs on the injector plugs and FICM module connectors become brittle and break off, allowing pins to vibrate loose. This causes intermittent open-circuit fault codes (DTCs P0261 through P0284), erratic injector buzz tests, random cylinder misfires, unburnt fuel smoke, and severe engine bucking under load. The genuine Motorcraft 4C3Z-9D930-AA eliminates wiring dropouts by providing brand-new locking terminals and high-temperature protective sleeving.

Fitment

• 2004 Ford F-250 Super Duty 6.0L Powerstroke Turbo Diesel (Built 12/02/2003 to 04/10/2004)
• 2004 Ford F-350 Super Duty 6.0L Powerstroke Turbo Diesel (Built 12/02/2003 to 04/10/2004)
• 2004 Ford F-450 Super Duty 6.0L Powerstroke Turbo Diesel (Built 12/02/2003 to 04/10/2004)
• 2004 Ford F-550 Super Duty 6.0L Powerstroke Turbo Diesel (Built 12/02/2003 to 04/10/2004)
• 2004 Ford Excursion 6.0L Powerstroke Turbo Diesel (Built 12/02/2003 to 04/10/2004)
• Fitment Note: Critical production date verification required (check door jamb certification label). Vehicles built on or before 12/01/2003 utilize part # 3C3Z-9D930-AA; vehicles built on or after 04/11/2004 utilize part # 5C3Z-9D930-A.

Safety & Power Cutoff: Park on level surface, turn off the ignition, and disconnect both negative battery cables. Allow the engine valley and cooling components to fully cool. Clearance Disassembly: Remove the air intake filter assembly, intake elbow, and upper intercooler (CAC) tube on the driver side to expose the FICM mounting bracket and cylinder head rocker harness paths. Module & Sensor Disconnection: Press the release latches on the three (3) main FICM connectors located beneath the FICM module and disconnect them. Unplug the connected sensors (such as the EBP sensor and oil temp sensor branches) and remove any chassis retaining clips. Injector Terminal Extraction: Depress the wire locking bails on each of the eight (8) fuel injector connectors along the rocker covers. Carefully unroute the old harness from valve cover retaining saddles and lift it out of the engine compartment. New Harness Routing: Lay the Motorcraft 4C3Z-9D930-AA into position along the driver and passenger rocker covers. Route each cylinder branch cleanly to its corresponding injector number. Firmly press each injector plug onto its terminal until the lock bails engage with an audible click. FICM Connector Engagement: Insert the three main module connectors into their corresponding keyed slots on the underside of the FICM. Push firmly until each latch locks into its retained detent. Grounds & Heat Shielding: Secure all harness ground eyelets to their factory engine/chassis ground locations and torque to 8–10 ft-lbs (11–13 Nm). Snap the harness conduit clips into the factory valve cover brackets, ensuring lines do not contact hot up-pipe or turbo housings. Diagnostic Verification & Startup: Reinstall CAC piping, intake ducting, and reconnect negative battery terminals. Key on (KOEO) and clear any stored injector circuit trouble codes using an OBD-II diagnostic tool. Perform an injector buzz test to confirm all 8 solenoids actuate crisply, then start the engine and verify smooth idle with steady 48V FICM main power.