Power Steering Service

This procedure covers the inspection and maintenance of the Electric Power Assist Steering (EPAS) system on the 2015-2020 Ford F-150 with 5.0L V8 engine, which uses an electric motor instead of hydraulic fluid.

Warnings

Tools required

Parts

• Battery terminal protector spray × 1 — Use OEM specification
• Electrical contact cleaner × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and set parking brake
2. Turn ignition off and remove key
3. Allow engine to cool if recently driven
4. Verify complaint: check for steering noise, difficulty turning, or warning lights
5. Connect scan tool and retrieve any stored diagnostic trouble codes (DTCs) related to steering system

Procedure

1. 1

   Disconnect Battery Negative Terminal
   Open hood and locate battery. Use 10mm wrench or socket to loosen negative battery terminal clamp. Remove cable and secure away from battery post to prevent accidental reconnection during service.
2. 2

   Inspect EPAS Motor and Connectors
   Locate the electric power steering motor mounted on the steering column under the dash. Inspect the main electrical connector for corrosion, damage, or looseness. Check connector locking tab is fully engaged. Look for any signs of water intrusion or pin damage.
3. 3

   Check Steering Column Mounting
   Inspect steering column mounting bolts and brackets for proper torque and no signs of looseness. Check for any play or abnormal movement in the column. Verify mounting points are not cracked or damaged.
   ⚠Do not loosen steering column mounting bolts unless replacement is required. Improper installation can affect airbag deployment and column collapse function.
   Torque spec

   Mounting Bolts34 Nm (25 lb-ft)

   Bracket Bolts26 Nm (19 lb-ft)
4. 4

   Inspect Intermediate Shaft and U-Joints
   Check the intermediate steering shaft from column to rack for proper U-joint condition. Look for wear, binding, or looseness. Rotate steering wheel lock-to-lock while observing shaft movement for any binding or noise. Check that shaft is properly lubricated at serviceable points.
5. 5

   Verify Steering Rack Mounting
   From underneath vehicle, inspect steering rack mounting bolts and bushings. Check for proper torque, no looseness, and intact bushings. Look for any fluid leaks (should be none on EPAS system), damage to rack boots, or signs of impact.
   Torque spec

   Mounting Bolts34 Nm (25 lb-ft)
6. 6

   Clean Electrical Connections
   Using electrical contact cleaner, spray and clean the EPAS motor connector terminals. If corrosion is present, disconnect connector and clean both male and female pins with contact cleaner and allow to dry. Reconnect ensuring positive engagement and locking tab clicks into place.
   Torque spec

   Connector Bolts8 Nm (6 lb-ft)
7. 7

   Check Ground Connections
   Locate steering system ground points on the frame and column. Verify ground connections are clean, tight, and free of corrosion. Use wire brush to clean ground contact surfaces if necessary. Ensure proper metal-to-metal contact.
8. 8

   Reconnect Battery and Clear Codes
   Reconnect negative battery terminal and tighten securely. Turn ignition to ON position (engine off). Using scan tool, clear any stored DTCs related to steering system if they were caused by disconnection or service procedures.
9. 9

   Perform Steering Angle Sensor Calibration
   With scan tool, access steering angle sensor calibration procedure. Start engine and follow scan tool prompts to center steering wheel and calibrate sensor. This ensures proper EPAS operation and prevents false warning lights. Procedure typically requires turning wheel fully left, then fully right, then center.
   ℹ️Steering angle sensor calibration is critical for proper EPAS and stability control function. Follow scan tool instructions exactly.

Reassembly

1. Verify all electrical connectors are fully seated and locked
2. Ensure no tools or parts were left in engine compartment or under vehicle
3. Double-check battery terminal is tight and secure

Verification

• Start engine and verify no warning lights on instrument cluster related to steering or stability control
• Turn steering wheel lock-to-lock while stationary - should be smooth with no binding or unusual noises
• Test drive vehicle at various speeds, confirming normal power assist function and no unusual steering behavior
• Verify steering wheel returns to center properly after turns
• Re-scan with diagnostic tool to confirm no DTCs present
• Confirm steering wheel is centered when driving straight

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