What it means
The TCM detects an electrical fault on transmission pressure control solenoid K. Hydraulic pressure cannot be modulated as expected, causing harsh or slipping shifts.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Pressure control solenoid K is an electrically controlled valve used to regulate pressure in a transmission hydraulic circuit. The TCM detects an electrical fault in solenoid K’s circuit, so it may not be able to control that pressure as expected. The resulting pressure error can cause harsh or slipping shifts.
Common causes
Most likely first.
- Internal solenoid fault
- Wiring or connector fault
Symptoms
- Check-engine or transmission warning light
- Harsh or delayed shifts
- Transmission may slip or hesitate
- Transmission may enter limp mode
How to diagnose it
- Read transmission codes and freeze-frame data, then check live data for solenoid K commands and any electrical fault status recorded by the TCM.
- Inspect the solenoid K connector and accessible harness for loose pins, corrosion, damaged insulation, or fluid intrusion.
- Check the solenoid K circuit and coil using the manufacturer’s electrical test procedure and specifications.
- Test circuit continuity and check for unintended shorts between the solenoid K wiring, ground, and power as directed by the wiring diagram.
- If wiring and solenoid checks pass, follow the manufacturer’s procedure to assess the TCM output and its connector.
Common fixes
- Clean and secure a loose or contaminated solenoid K connector.
- Repair damaged wiring or corroded terminals in the solenoid K circuit.
- Replace solenoid K if its coil fails the manufacturer’s electrical checks.
- Repair the TCM circuit or module if testing confirms its output is faulty.
Can I keep driving?
Avoid towing and hard acceleration until the electrical fault is fixed, since solenoid K may not regulate pressure and the transmission can shift harshly, slip, or enter limp mode. Stop if it loses drive or slips severely.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.