FORD Explorer High-Speed Cooling Fan Motor RELAY Overheating

FORD Explorer High-Speed Cooling Fan Motor RELAY Overheating

A damaged non-functional relay, causing the fan to never turn on may lead to engine overheating at idle.

Models

2016-2018 Ford Explorer build in Chicago Assembly Plant from 9/19/2014-12/1/2017

Reference Number: 21N01

After extended idling, the high-speed cooling fan relay may fail in some of the affected vehicles. A failure will cause the fan to either continuously run or never turn on. A continuously running fan will increase the temperature of the relay’s connections (terminals) to beyond their design maximum. This may eventually create an electrical arc which heats and damages the relay terminals. Customers may experience a drained battery and a non-functional or even a melted/burned high-speed cooling fan relay inside the battery junction box (BJB). A damaged non-functional relay, causing the fan to never turn on may lead to engine overheating at idle.

Service Action

Dealers are to replace (splice) the four affected high-speed cooling fan relay terminals in the BJB and reroute the new terminals to a new larger relay. This service must be performed on all affected vehicles at no charge to the vehicle owner. Detailed repair instructions can be found in the TSB. This program provides a no-cost, one-time repair (if needed) to the high-speed cooling fan relay and respective electrical terminals, if affected, to 10 years of service or 150,000 miles from the warranty start date of the vehicle. This is a one-time repair program. If a vehicle has already exceeded either the time or mileage limits, this no-cost, one-time repair will last through August 31, 2022.

Program eligibility is automatically transferred to subsequent owners.

You May Also Like

Electronic Throttle Body Service

On most systems, idle speed is completely controlled by the throttle plate angle.

The electronic throttle body is very similar to the cable-operated throttle body, with a few notable changes. Among the most noticeable is the addition of the throttle actuator control motor. This motor is used to open and close the throttle plate based on direct commands from the engine control module.

Spark Plug Replacement

Here are some tips to follow when replacing a spark plug.

Transmission Fluid Hydraulics

You need to know how transmission fluid flows inside an automatic transmission.

How ADAS Systems Perform

When new technologies are applied to driver safety, a higher level of scrutiny and service is required.

Air Ride Suspension Diagnostics

The key to understanding the embedded logic of air ride systems is using service information.

Other Posts
Steering Angle Sensor 101

The steering angle is used by many ADAS functions.

BMW N54 Turbo Problems

Here are some common problems or failures that you should be on the lookout for.

Mercedes-Benz Engine Oil Leaks

Mercedes makes a fine product, but certain repairs will emerge as trends over time.

Brake Pad Wear Sensors

Brake pad wear sensors have been around for years and continue to evolve.