Wiring Diagrams — Ford F-150 1987-1991
Technical Reference
Member-uploaded diagrams & documents for this generation. AI-classified; community-verified where badged.
Wiring Diagrams
- Wiring diagram of the Ford 5.0L/5.8L electronic engine control and ignition circuit with color-coded wires and connector labels.
- Wiring diagram for the 4.9L EFI EEC control system showing relays, sensors, injectors, and color-coded circuits.
- Wiring diagram of the horn circuit showing the horn relay, fuse box, keyless entry and high and low pitch horns.
- Start/glow plug run schematic showing ignition switch terminals, fuse links U and V, fuel line heater, fuel shutoff solenoid, cold idle/advance solenoids, and engine temperature sensor.
- Start/glow plug control schematic showing batteries, starter relay/solenoid, glow plug controller, glow plugs, and the wait-to-start indicator circuit with wire gauges and colors.
- Automotive wiring diagram page for diesel charge and power distribution with color-coded wires, connectors and fuse panel.
- Diesel charge/power-distribution schematic showing alternator output to splice S220, charge indicator lamp, main light switch, headlamps and courtesy/dome lamp circuits.
- Diesel charge/power distribution schematic for an F-350/Super Duty showing battery, starter relay, starter solenoid, alternator/regulator, fuse links, and wire gauges/colors.