Pinpoint Test I : Line Pressure Control (LPC) Solenoid A: Notes
WARNING: This page is about a different car, the 2015 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
Refer to Transmission Controls - 6F35 for schematic and connector information.
Normal Operation
The PCM controls the hydraulic line pressure by varying the amount of current applied to the Line Pressure Control (LPC) solenoid A. When no current is applied to the Line Pressure Control (LPC) solenoid A, the LPC solenoid A is fully opened, resulting in the maximum amount of hydraulic pressure to the main pressure regulator valve. When maximum current is applied, the Line Pressure Control (LPC) solenoid A is fully closed, resulting in minimum pressure to the main pressure regulator valve.
NOTE:
Without a voltage signal return to the PCM, the transmission solenoid power control relay is commanded off. Using a fused jumper wire between a transmission solenoid control circuit and the signal return circuit, the transmission solenoid power control relay circuit supplies power to the transmission solenoids when the ignition is cycled from off to on. Do not use a solenoid control circuit that may be at fault, refer to DTC Charts for a fault listing.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| P0748 | Pressure Control Solenoid "A" Electrical | Line pressure control solenoid electrical circuit general fault. May set along with DTC P0960, P0962 and P0963. |
| P0960 | Pressure Control Solenoid "A" Control Circuit/Open | Open circuit in solenoid or solenoid circuitry. |
| P0961 | Pressure Control Solenoid "A" Control Circuit Range/Performance | Intermittent short to ground in solenoid or solenoid circuitry. |
| P0962 | Pressure Control Solenoid "A" Control Circuit Low | Short to ground in solenoid or solenoid circuitry. |
| P0963 | Pressure Control Solenoid "A" Control Circuit High | Short to power in solenoid circuitry. |
Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- Line Pressure Control (LPC) A solenoid
- Transmission internal wiring harness frame
- PCM