Code 11 - Stoplight Operation
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1988 Ford Pickup, 1988 Ford Cab & Chassis, 1988 Ford Bronco II, 1988 Ford Bronco, and 1987 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
Check stoplight fuse, stoplight switch adjustment and wiring. If system is okay, unplug computer module connector. Check voltage between terminal No. 11 and ground with brake pedal is depressed. If there is no voltage, repair open wire. If voltage is 8-13 volts, check stoplight and turn signal wiring. Repair as necessary.