How to Replace the Fog Lamps Relay in a 2008 Ford Explorer

Disconnect the battery. You run the risk of an accidental electrical surge that could hurt you or cause costly damage to your vehicle if you leave it connected during repair.

Locate the power distribution box in the engine compartment that houses your Ford Explorer's fog lamps relay. The box rests to the right of the compartment behind the battery.

Unlatch the power distribution box cover and push up. You don't need to remove the lid, as it can rest vertical to the box while you work.

Unplug your fog lamps relay located in the bottom right corner of the box (labeled as the 50A block on your power distribution box diagram). Then, check the box area for dirt, corrosion or damage that could cause the relay to malfunction and clean or repair any area, as needed.

Plug your replacement Ford Explorer fog lamps relay firmly into the empty relay socket. Make sure it's not loose, as current running through a loose relay can cause the relay to overheat or the outer casing and surrounding relay casings/box cover to melt. Afterward, push your power distribution cover down until it locks firmly into place.

Reconnect your battery. As the Ford Explorer has an adaptive learning computer, you must reset the computer as follows before testing the relay: set the parking brake and gearshift to park, turn off all accessories, start and then idle your engine for at least one minute, turn on your air conditioning and continue to allow the engine to idle.

Test the fog lamps to see if the relay corrected the fog lamps malfunction. If the lamps work, continue with your computer reset by driving your Ford Explorer (to help the transmission relearn). Lastly, reset the clock and radio presets.