Pinpoint Test R: Transmission Solenoid Power Control: Notes

Diagnostic Overview

Diagnostics in this article 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 - 6F50/6F55 for schematic and connector information.

Normal Operation and Fault Conditions

The transmission solenoid power control relay controls vehicle power to all solenoids. Power is routed through the transmission solenoid power control relay (inside the PCM) to all transmission solenoids. If the power circuit to the transmission solenoids or the transmission solenoid power control relay fails open, all solenoids are failed electrically off. Check for open, short to ground or the transmission connector disconnected. The transmission solenoid power control relay disables power to the transmission solenoids when certain transmission DTCs are set.

NOTE: Without a voltage signal return to the PCM, the transmission solenoid power control relay is commanded off. By 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-PCM for a fault listing.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Conditions
P0657	Actuator Supply Voltage "A" Circuit Open	Open circuit on the transmission solenoid power circuit.

Possible Sources

Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
PCM