What it means
The control module monitors the control circuit for shift solenoid A. It sets this code when it detects an open circuit in that control path.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Shift solenoid A is an electrically operated valve that directs transmission fluid for gear changes. The control module monitors the A control path and sets P097A when it detects an open circuit, interrupting current to the solenoid. The break can be in the wiring, connector, or solenoid A coil.
Common causes
Most likely first.
- Open in solenoid control wire
- Open solenoid coil
- Pin pushed back out of connector body
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Save freeze-frame data and check transmission live data for the shift conditions when the solenoid A open was detected.
- Inspect the solenoid A connector for a pushed-back pin, a loose lock, corrosion, or a disconnected plug.
- Follow the solenoid A control wire and look for breaks, damaged insulation, or a poor splice.
- Test continuity through the A control wire and connector, isolating the circuit as specified in the wiring diagram.
- Measure solenoid A coil resistance and compare it with the manufacturer’s specification to identify an open coil.
- Check module output only after the A wire, connector, and coil have been verified.
Common fixes
- Reseat or repair a pushed-back or loose terminal at the solenoid A connector.
- Repair an open or broken solenoid A control wire or connection.
- Replace shift solenoid A if its coil is open.
- Repair or replace the transmission control module if testing confirms it is not providing the specified control.
Can I keep driving?
An open solenoid A circuit can cause missed or harsh shifts and may put the transmission into limp mode; avoid long trips and heavy loads. Stop if the vehicle slips or cannot maintain a safe gear, since continued driving can worsen damage.
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.