1988 Ford F-250 Diesel Start/Glow Plug Control Wiring Diagram - EVTM Page 31

This is page 31 of a Ford Electrical & Vacuum Troubleshooting Manual (EVTM) showing the Start/Glow Plug Control/Run circuit wiring diagram for a diesel engine. The diagram traces power from circuit 37 Y through splice S208 to the ignition switch (with ACCY, START, RUN, LOCK, OFF positions and BATT, I1, I2, ST terminals; the reader is referred to page 124 for switch terminal details). From terminal I1, circuit 16 R/LG feeds through splice S216 and connector C100 to fuse link V and fuse link U (both 20 GA blue). Circuit 262 BR/PK comes from terminal I2, and circuit 32 R/LB from terminal ST goes to the start/ignition circuit on page 26; a branch also goes to charge/power distribution on page 22. Downstream loads shown include the fuel line heater (circuits 34 DB, 30 R/LG through connector C129 and splice S156), the fuel shutoff solenoid (30 R/LG), and — via circuit 42 R/LG through the engine temperature sensor, which closes below 62°C (112°F) — the cold idle solenoid and cold advance solenoid on circuits 44 R/Y and 46 R/Y. A reader can learn wire gauges, colors, circuit numbers, splice/connector IDs, and component interconnections for diesel start and glow plug operation.