What does it mean?
P1775 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: A/T Torque Converter Clutch Solenoid Circuit Low Input .
Symptoms
- MIL (check engine lamp) is on and torque converter lockup is disabled
- Engine speed sits high at steady cruise and fuel consumption rises
- Converter shudder or a vibration felt through the floor at light throttle
- If the solenoid is stuck applied, the engine stumbles or stalls as the vehicle comes to a stop
- Transmission fluid overheats on long runs
- Transmission may fall into limp mode
Likely causes
- Short to ground on the converter clutch solenoid control wire, often where the harness passes a sharp bracket
- Solenoid winding shorted internally, giving abnormally low resistance and high current
- Harness inside the transmission rubbed through against the case or valve body
- Corroded case connector, with fluid or moisture creating a low-resistance path between pins
- Debris in the solenoid bore, so the valve jams and current draw stays high
- Control module output driver shorted low
- Poor module ground raising apparent circuit current
How to fix it
- Read the freeze frame and note the speed, load and temperature at which the fault set
- Check the fluid level and condition before disturbing anything
- Measure solenoid resistance at the case connector; a value well below specification points to a shorted winding
- Unplug the solenoid and check the control wire on its own for a short to ground along the whole run
- Check the module output voltage while commanding lockup, with the solenoid disconnected and then connected
- Repair the shorted wire or replace the solenoid or valve body; verify slip drops on a road test after repair