Pinpoint Test F : Transmission Solenoid Power Control
- 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.
Refer to Transmission Controls - 6F35 for schematic and connector information.
Normal Operation and Fault Conditions
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 diagnostic trouble codes (DTCs) are set.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P0657:00 Actuator Supply Voltage "A" Circuit/Open: No Sub Type Information Open circuit on the transmission solenoid power circuit. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- Transmission internal wiring harness frame
- PCM
- F1 CHECK THE TRANSMISSION SOLENOID POWER CONTROL CIRCUIT
- Ignition OFF.
- Disconnect Transmission Vehicle Harness C1520A.
- Inspect the connectors for damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.
-
NOTE: Use a meter with a min/max feature and/or recording capabilities to obtain accurate measurements. The PCM disables the voltage output immediately if the shift solenoid return circuits are not present.
Connect the meter to C1520A-5 harness side and ground.
- Enable the min/max or recording feature.
- Ignition ON.
- Check the maximum recorded voltage on the meter.
Positive Lead Measurement / Action Negative Lead C1520A-5 Ground
Is the maximum recorded voltage greater than 11 volts?
Yes GO to F4 No GO to F2 - F2 CHECK THE TRANSMISSION SOLENOID POWER CONTROL CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect PCM C1915E.
- Inspect the connectors for damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals.
Is the resistance less than 3 ohms?
Yes GO to F3 No REPAIR the circuit. - F3 CHECK THE TRANSMISSION SOLENOID POWER CONTROL CIRCUIT FOR A SHORT TO GROUND
- Measure:
Positive Lead Measurement / Action Negative Lead C1520A-5 Ground
Is the resistance greater than 10, 000 ohms?
Yes Refer to PCM Guided Routine Testing . After installing a new PCM, CARRY OUT the transmission strategy download. REFER to: Transmission Strategy Download . No REPAIR the circuit. - Measure:
- F4 CHECK THE SOLENOID BODY LEADFRAME FOR A SHORT TO GROUND
- Ignition OFF.
Is the resistance greater than 10, 000 ohms?
Yes GO to F5 No INSTALL a new transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame . - F5 CHECK THE SOLENOID BODY LEADFRAME FOR AN OPEN
- Remove the transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame . Inspect for metal shavings on the exposed metal contacts or other components and clean the solenoid and transmission internal wiring harness frame terminals.
- Measure:
Positive Lead Measurement / Action Negative Lead Transmission internal wiring harness frame pin 5. Transmission internal wiring harness frame all pin fives.
Are the resistances less than 3 ohms?
Yes Refer to PCM Guided Routine Testing . After installing a new PCM, CARRY OUT the transmission strategy download. REFER to: Transmission Strategy Download . No INSTALL a new transmission internal wiring harness frame. REFER to: Transmission Internal Wiring Harness Frame .