Replace the coolant temperature sensor on a 2015-2020 Ford F-150 with 5.0L Coyote V8 engine to restore accurate temperature readings and proper engine management.

Warnings

Tools required

Parts

• Engine coolant temperature sensor × 1 — Motorcraft DY1250 or equivalent
• O-ring seal (if not included with sensor) × 1 — Check sensor kit contents
• Dielectric grease × 1 — Small packet

Fluids

• Motorcraft Orange Coolant — 1.5 qt

Preparation

1. Ensure engine is completely cold to the touch (at least 2 hours after last operation)
2. Park vehicle on level surface and engage parking brake
3. Place drain pan under the driver side front of the engine to catch coolant spillage
4. Have replacement sensor and tools ready before draining coolant

Procedure

1. 1

   Relieve cooling system pressure
   Slowly turn the radiator cap counterclockwise to the first stop and allow any residual pressure to escape. Wait until all hissing stops, then remove the cap completely. This prevents coolant from spraying when the sensor is removed.
2. 2

   Drain coolant below sensor level
   Open the radiator drain petcock at the bottom of the radiator on the driver side by turning counterclockwise. Drain approximately 2 quarts of coolant or until the level is below the sensor location on the cylinder head. The sensor is located on the front driver side of the cylinder head.
   Torque spec

   Drain Petcock8 Nm (6 lb-ft)
3. 3

   Locate and access the coolant temperature sensor
   The ECT sensor is mounted on the driver side cylinder head near the front. It has a single electrical connector. You may need to move aside wire harnesses or hoses for better access. Use a flashlight to confirm sensor location before proceeding.
4. 4

   Disconnect electrical connector
   Press the locking tab on the electrical connector and pull straight back to disconnect from the sensor. Do not pull on the wires. If the connector is tight, gently wiggle while pulling. Inspect connector terminals for corrosion.
5. 5

   Remove old coolant temperature sensor
   Using a 19mm deep socket and ratchet, turn the sensor counterclockwise to remove. Expect a small amount of coolant to drain from the opening. Keep the drain pan positioned underneath. Remove the sensor completely and inspect the O-ring seal.
6. 6

   Prepare sensor bore
   Clean the sensor mounting hole in the cylinder head with a shop towel. Remove any old O-ring material or debris. Use a wire brush or emery cloth if necessary to ensure a clean seating surface. Do not allow debris to fall into the coolant passage.
7. 7

   Install new sensor
   Verify the new O-ring is properly seated on the new sensor. Lightly coat the O-ring with fresh coolant (not grease). Thread the sensor in by hand clockwise until it seats against the cylinder head. Use the 19mm socket and torque wrench to tighten to 12-15 Nm (9-11 lb-ft). Do not overtighten as this can damage the sensor or cylinder head threads.
8. 8

   Reconnect electrical connector
   Apply a small amount of dielectric grease to the sensor terminal. Push the electrical connector onto the sensor until it clicks into place. Gently tug on the connector to verify it is locked. Ensure the wire routing does not create tension on the connector.
9. 9

   Close drain and refill coolant
   Close the radiator drain petcock by turning clockwise hand-tight. Using a funnel, slowly refill the cooling system through the radiator opening with Motorcraft Orange Coolant (50/50 premix or properly mixed). Fill until coolant is visible at the radiator neck.
   Torque spec

   Drain Petcock8 Nm (6 lb-ft)
10. 10

    Bleed air from cooling system
    Start the engine with the radiator cap off. Allow it to idle and warm up to operating temperature while monitoring coolant level. Add coolant as the level drops when air purges from the system. Run the heater on high to help purge air. When the thermostat opens (upper radiator hose becomes hot), the coolant level will drop significantly - top off as needed.
11. 11

    Complete fill and install radiator cap
    Once engine reaches full operating temperature and no more air bubbles are visible, top off coolant to the base of the radiator neck. Install the radiator cap securely. Check the coolant overflow reservoir and fill to the COLD FILL line if needed.

Reassembly

1. Verify all electrical connections are secure and properly routed
2. Confirm radiator cap is installed and tight
3. Wipe down any coolant residue from engine components and frame

Verification

• Start engine and verify coolant temperature gauge reaches normal operating range within 5-10 minutes
• Check for coolant leaks around the sensor with engine at operating temperature
• Use a scan tool to verify ECT sensor reading matches actual engine temperature (should read approximately 180-220°F at operating temperature)
• Verify no check engine light illuminates and no temperature-related fault codes are present
• Recheck coolant level after engine cools completely and top off if necessary

More procedures for this vehicle