Some 2007 Ford Edge and Lincoln MKX models may produce a burning odor while being driven.
The smell may be accompanied by a low power complaint and an illuminated Integral Vehicle Dynamics (IVD) light on the dash. One likely cause is brake drag. How to deal with it depends on which wheels are binding.
Start the diagnosis by getting the vehicle on a lift. Now spin each wheel by hand to see where the drag is taking place. If all four wheels are affected, chances are good the brake switch is sticking, which causes the hydraulic circuits to stay pressurized with no change in the brake on/off input status from the switch to the module. That's what causes the IVD light on the dash to illuminate.
To confirm that the brake switch is causing the drag, lower the vehicle, disconnect the harness from the switch and rotate the switch clockwise. If the brake pedal suddenly moves up, the switch plunger is jammed. Replace the brake switch with an upgraded unit, Part No. 8T4Z-13480-A, making sure the brake lights work properly when pushing down on the pedal.
If only the rear wheels bind when spinning the wheels, the parking brake equalizer is likely misadjusted. Make sure the parking brake pedal is fully released, then adjust the equalizer until both rear wheels rotate freely. For your information, the distance between the cable nut and stud should be about 7/8-inch.
"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected].