P288A: Park Lock/Pawl Actuator Circuit High

What it means

Voltage on the park lock/pawl actuator control circuit is above the expected range. The code identifies a circuit condition; it does not by itself identify the failed component.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

The park lock or pawl actuator circuit drives the mechanism that holds the transmission in Park. P288A sets when the control module detects voltage above the expected range on that control circuit; a high reading may result from a short to battery voltage or an open actuator coil.

Common causes

Most likely first.

1. Control wire shorted to B+
2. Open actuator coil
3. Connector pins corroded - high contact resistance

Symptoms

• Transmission warning light on
• Difficulty shifting into or out of Park
• Park position may not engage or release as expected

How to diagnose it

1. Save freeze-frame data and related transmission codes to see whether the high reading occurred during a Park actuator command.
2. Inspect the actuator wiring for damage that could let the control wire contact battery voltage, and check the connector for corrosion or loose pins.
3. Using the manufacturer's wiring diagram, measure the control circuit during a command and compare the reading with the specified range.
4. With power isolated as directed by service information, check the actuator coil for an open circuit and inspect connector contact condition.
5. If the wiring and actuator test correctly, check the control module output and its connector for a fault.

Common fixes

• Repair a control wire shorted to battery voltage.
• Repair corroded, loose, or damaged actuator connector pins.
• Replace the actuator if its coil is open.
• Repair the control module output circuit if testing confirms it is responsible for the high reading.

Can I keep driving?

Apply the parking brake and do not rely on Park if it fails to engage or release consistently. Avoid driving when Park operation is unreliable, because the parking mechanism may not secure the vehicle.