PINPOINT TEST D : TCS (Tow Haul): Notes
Diagnostic Overview
Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Service Information for information about these practices.
Refer to TRANSMISSION CONTROLS SYSTEM - 6F35 for schematic and connector information.
Normal Operation and Fault Conditions
The TCS (Tow Haul) is a momentary contact switch located in the center stack switch assembly. Pressing the Tow Haul switch will engage or disengage the Tow Haul function of the transmission. When the Tow Haul is engaged, the Tow Haul icon will illuminate on the IPC. Each time the ignition switch is cycled, the TCM will disengage the Tow Haul operation regardless of the switch position the last time the engine was running.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| P1780 | Transmission Control Switch (O/D Cancel) Circuit Out Of Self Test Range | The TCS (Tow Haul) failed during the KOER self-test. |
Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.
- Fuse 41 (7.5A)
- Tow Haul switch
- TCM