Confirmation Procedure

1. Start the engine.

2. Hold the engine speed at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.Test-drive the vehicle under these conditions:

• HDS [ECT Sensor 1] above 158 deg.F (70 deg.C)
• Transmission in D
• Vehicle speed between 45 - 75 mph (70 - 120 km/h) for 5 minutes or more with cruise control set
• Vehicle speed between 55 - 75 mph (90 - 120 km/h) for 10 seconds, then decelerate (with the throttle fully closed). Repeat this three or more times
• Maintain the vehicle speed at 55 mph (90 km/h) for 4 minutes or more with cruise control set

4. Monitor the [OBD STATUS] for DTC P0420.