how to resolve U0420 code on Ford F-150 Fourteenth Generation (2021-present)

Learn how to diagnose and fix U0420 invalid data received issue in Ford F-150. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the vehicle is on a flat surface and secured with wheel chocks.

2. Inspect Wiring and Connectors

• Tools Required: Multimeter, wire brush, electrical contact cleaner
• Visually inspect the wiring harness connected to the vehicle dynamics control module for any signs of fraying or wear.
• Use a multimeter to check for continuity in the wires.
• Clean any corroded connectors with electrical contact cleaner and a wire brush.

3. Replace Vehicle Dynamics Control Module (if necessary)

• Tools Required: Socket set, torque wrench
• Remove any covers or components blocking access to the vehicle dynamics control module.
• Disconnect the connector from the module and remove the mounting bolts.
• Install the new module by reversing the removal steps, ensuring all connections are secure.
• Torque the mounting bolts to the manufacturer’s specifications (typically found in the service manual).

4. Reconnect Battery and Reprogram Module

• Reconnect the negative battery terminal.
• Use the diagnostic tool to reprogram the new vehicle dynamics control module, following on-screen instructions.

5. Clear Diagnostic Codes

• Use the OBD-II scanner to clear the U0420 code from the vehicle’s computer.
• Perform a test drive to ensure that all systems are functioning correctly.