P0627 on 2018-2024 Ford Expedition: Fuel Pump Control Circuit Causes and Fixes

What's Unique About the 2018-2024 Ford EXPEDITION

For this generation of Ford Expedition and its platform mates, the P0627 code is so commonly linked to a specific issue that Ford has issued multiple Technical Service Bulletins (TSBs). The problem is frequently not the fuel pump or the control module itself, but rather a poor connection where the wiring harness plugs into the Fuel Pump Control Module (FPCM). This connection (connector C433) is exposed to the elements under the vehicle on a rear frame cross-member, making it susceptible to moisture and corrosion which can interrupt the signal and trigger the code.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Engine will not start
• Engine cranks for a long time before starting
• Engine stalls intermittently while driving, sometimes after hitting a bump
• Loss of engine power or sluggish acceleration
• Illuminated Check Engine Light
• Rough idle before stalling

Most Likely Causes

1. Poor Connection at Fuel Pump Control Module (FPCM) 🔴 High Probability The FPCM is mounted to the vehicle's frame cross-member above the spare tire, exposing its electrical connector to moisture, road salt, and vibration. This leads to corrosion, pushed-out pins, or an incompletely seated connector, as documented in Ford TSBs SSM 52483, 50841, and 51306. Forum users report finding the connector full of water or showing green/white corrosion on the pins.
   How to confirm: Visually inspect the FPCM connector (C433 or C4033) for signs of corrosion, moisture, or backed-out pins. Unplug the connector, checking that the gray locking tab moves freely, and clean both sides with electrical contact cleaner. Also, locate and inspect the main ground for the module (G403 or G406 on the frame nearby) for tightness and corrosion.
   Typical fix: Clean the connector terminals and apply dielectric grease to prevent future moisture intrusion. Ensure the connector is securely latched with an audible click. Tighten or clean the ground connection. In many cases, this resolves the code without replacing any parts.
   Est. part cost: $0-$15
2. Failed Fuel Pump Control Module (FPCM) 🟡 Medium Probability The same environmental exposure that damages the connector can also cause the module itself to fail. Some owners on forums note that the aluminum housing of the module can corrode where it bolts to the steel frame, potentially allowing moisture inside. An owner complaint to the NHTSA for a 2021 model resulted in the replacement of the control unit. [ODI #11675577]
   How to confirm: If cleaning the connector and ground does not resolve the issue, and power/ground inputs to the module are verified with a multimeter, the module itself is the likely culprit. A scan tool capable of communicating with the FPCM can also help confirm a module failure.
   Typical fix: Replace the Fuel Pump Control Module. This is a bolt-on part, but it is recommended to use a genuine Motorcraft part for reliability. The OEM part number is often a successor to the original, such as JL3Z-9D370-B or HL3Z-9D370-B.
   Est. part cost: $65-$150
3. Failed In-Tank Fuel Pump ⚪ Low Probability While less common for this specific code, an internal failure in the fuel pump's electronics can create an open circuit. A 2022 Expedition was included in a recall for failing low-pressure fuel pumps. An NHTSA complaint also documented a fuel pump failure alongside the control unit. [ODI #11675577] However, this is often misdiagnosed when the real issue is the FPCM connection.
   How to confirm: After confirming the FPCM and its wiring are good, the next step is to test the fuel pump. This can involve checking for the command voltage from the FPCM at the pump connector or measuring fuel pressure.
   Typical fix: Replace the in-tank fuel pump assembly, which requires dropping the fuel tank.
   Est. part cost: $250-$500

Rare But Worth Checking

• Damaged Wiring Harness: Check for chafed or broken wires along the frame rail between the PCM (engine bay) and the FPCM (rear of vehicle), especially near any sharp edges or suspension components. The harness has been noted to be short, making it difficult to inspect without tension.
• Blown Fuse: Check the fuse for the fuel pump circuit in the vehicle's fuse box. While a blown fuse is a simple fix, it often indicates a deeper electrical problem (like a short circuit) that caused it to blow.

Diagnosis Steps

1. Scan for all DTCs. Note if P0627 is accompanied by U0109, P025A, P00C6, or P008A, as this strongly points to the FPCM circuit.
2. Check for relevant TSBs (SSM 52483, 51306, 50841) and recalls. Note the 2022 Expedition was part of a fuel pump recall.
3. Locate the Fuel Pump Control Module (FPCM) on the frame cross-member, typically above or near the spare tire.
4. Disconnect the FPCM electrical connector (C433/C4033). Inspect both the harness side and the module side for green/white corrosion, moisture, bent pins, or loose terminals.
5. Clean any corrosion found with a small brush and electrical contact cleaner. Apply dielectric grease to the connector seal before reconnecting firmly. Ensure the locking tab is fully engaged.
6. Locate and inspect the FPCM ground point (G403/G406) on the frame. Ensure it is clean, free of corrosion, and securely fastened.
7. If the problem persists, use a multimeter to check for 12V power and a good ground at the FPCM connector with the key on.
8. If power and ground are present but the code returns immediately, the FPCM is likely faulty and should be replaced.
9. If the FPCM and its wiring are confirmed to be good, the final step is to diagnose the in-tank fuel pump itself.

Parts You'll Likely Need

• Fuel Pump Control Module (OEM #JL3Z-9D370-B / HL3Z-9D370-B (verify with VIN, part numbers supersede)) — This module is the second most likely failure point after its own connector. It is exposed to the elements and can fail internally. Part number must be verified with the vehicle's VIN.
  Trusted brands: Motorcraft, Dorman
  OEM price range: $90-$150
  Aftermarket price range: $65-$110
• In-Tank Fuel Pump Assembly — If the module and wiring are confirmed good, the pump itself has likely failed. This is the most expensive and labor-intensive repair for this code.
  Trusted brands: Motorcraft, Bosch, Delphi
  OEM price range: $350-$500
  Aftermarket price range: $250-$400

Related Codes That Often Appear With This One

• U0109 — Stands for 'Lost Communication With Fuel Pump Control Module'. This code is frequently stored with P0627 because the open circuit prevents the PCM from communicating with the FPCM. [SSM 52483, SSM 50841, SSM 51306]
• P025A — Stands for 'Fuel Pump Module 'A' Control Circuit/Open'. This is another code pointing to the same electrical fault and is explicitly mentioned in the same TSBs as P0627. [SSM 52483, SSM 50841, SSM 51306]
• P00C6 — Relates to 'Fuel Rail Pressure Too Low'. This code can appear because the open control circuit prevents the fuel pump from building adequate pressure. [SSM 52483, SSM 50841, SSM 51306]
• P008A — Relates to 'Low Pressure Fuel System Pressure - Too Low'. Similar to P00C6, this indicates the fuel system is not reaching its target pressure, a direct consequence of the pump not being controlled correctly. [SSM 52483, SSM 50841, SSM 51306]

Technical Service Bulletins (TSBs) & Recalls

• SSM 52483 (April 25, 2024): Notes that P0627 and other codes may be caused by an intermittent or partial disconnect at the FPCM connector (C433/C4033) or a poor ground (G403/G406).
• SSM 50841 (June 8, 2022): Specifies the cause may be a disconnect at the FPCM connector, damaged pins, or loose/corroded grounds for 2018-2022 models.
• SSM 51306 (January 19, 2023): Supersedes previous TSBs, extending the model year coverage to 2023 and reiterating the same diagnostic advice to check the FPCM connection and ground first.

Platform-Specific Known Issues

• A series of Ford TSBs (SSM 52483, 51306, 50841) directly address P0627 on 2018-2024 Expeditions, pointing to an intermittent disconnect at the Fuel Pump Control Module connector (C433/C4033) or a bad ground (G403/G406) as the primary cause.
• A recall was issued for some 2022 Ford Expeditions for a failing low-pressure fuel pump, which could lead to an engine stall.

Mechanic-Grade Diagnostic Values

• FPCM Power Supply Voltage at Connector C4336, Pin 1 — expected: 12V+ (Battery Voltage) with Key On, Engine Off. Failure: 0V indicates an open circuit in the power supply wire between the fuse box and the FPCM.
• FPCM Ground Circuit Continuity — expected: Less than 1 ohm of resistance between the ground pin on the FPCM connector and a clean chassis ground point.. Failure: High or infinite resistance (OL) indicates a broken or corroded ground wire at G401/G403.
• FPCM Control Circuit Voltage (from PCM) — expected: A 12V pulse when the ignition is first turned on.. Failure: No voltage pulse suggests a problem with the PCM or the wiring between the PCM and FPCM.

Scan Tool Commands That Help

• Ford IDS / FORScan / High-End Bidirectional Scanner: FPCM/Fuel Pump Activation Test — Use this command to manually turn the fuel pump on and off. If the pump runs during this test, it confirms the FPCM, the pump itself, and the wiring between them are likely functional. This isolates the fault to the command signal from the PCM or the PCM itself.

Wiring & Ground Locations

• C433 / C4033 / C4336 — On the frame cross-member, typically located above the spare tire. It is the main electrical connector for the Fuel Pump Control Module (FPCM).. This is the single most common failure point. It is exposed to the elements, leading to corrosion, moisture intrusion, and pushed-out pins, directly causing an open circuit (P0627) and loss of communication (U0109) as cited in multiple Ford TSBs.
• G403 / G406 / G401 — On the frame rail near the FPCM, above the spare tire.. This is the primary chassis ground for the FPCM. If this connection is loose or corroded, the module cannot function correctly, leading to control circuit faults and communication codes.
• FPCM Connector Pin 1 — The first pin on the FPCM electrical connector (C433/C4336).. This is the main 12V power supply to the module. A documented repair found 0V at this pin due to a wire break further up the harness, even when the connector itself looked clean. It is a critical test point.

Real Owner Repair Stories

• YouTube channel 'FordTechMakuloco' (similar F-150 platform) (2021 Ford F-150) — Intermittent no-start that progressed to a permanent crank-no-start condition. Codes P0627 and U0109 were stored.
  ❌ Tried (didn't work) Visual inspection of the FPCM connector (no visible damage), Cleaning and tightening the G401 ground point
  ✅ What actually fixed it A voltage test at Pin 1 of the FPCM connector (C4336) showed 0V. The technician found a broken power supply wire further up the harness, hidden from view behind the fuel tank. Repairing the broken wire restored power to the module and fixed the issue.
• Ford F150 Forum (2015 Ford F-150 3.5L) — Truck started, then died when put in drive. Restarted but ran very rough and would die with any throttle input. Code P0627 present.
  ❌ Tried (didn't work) Initial diagnosis was uncertain.
  ✅ What actually fixed it The owner reported the issue was a damaged Fuel Pump Control Module, which was replaced to solve the problem.

OEM Part Supersession History

• HL3Z-9D370-A → HL3Z-9D370-B — Standard part revision by the manufacturer.
• M1PZ-9D370-A → PR3Z-9D370-B — Standard part revision by the manufacturer, often used on other platforms like Mustang but may be applicable.
  Heads up: Part numbers are platform-specific. Always verify the correct part number for an Expedition using the vehicle's VIN.