What it means
The shift lock solenoid for selector lever A stays engaged when release is commanded. Driver cannot move the selector out of Park or away from the locked gate.
At a glance
- Usually lights the check-engine light
How it works
Shift lock actuator A is part of the selector interlock that normally prevents the lever from leaving a locked gate, such as Park, until release conditions are met. P27F4 means the actuator remains engaged after the control system commands it to release, so the selector may stay locked.
Common causes
Most likely first.
- Lock actuator mechanically stuck
- Control driver stuck on
- Carbon or debris buildup preventing free movement
Symptoms
- Shift lever may be difficult or impossible to move out of Park
- Shift interlock or transmission warning light may come on
How to diagnose it
- Confirm the selector is in the position associated with the complaint and check whether the brake lamps work, since the interlock may depend on the brake switch input.
- Scan the transmission or body control module for shift-lock commands and related brake-switch or interlock codes.
- Inspect actuator A, its connector, and the selector area for debris, damage, or a mechanism that binds.
- Check the actuator A wiring and connector for shorts or damage that could keep it powered.
- Test whether the module’s release command changes at the actuator and compare circuit operation with the manufacturer’s specification.
Common fixes
- Remove debris that is physically obstructing actuator A or the selector mechanism.
- Repair a damaged or shorted actuator A wire or connector.
- Free or replace a mechanically stuck shift lock actuator A.
- Repair the control driver only if circuit testing confirms it is holding actuator A on.
Can I keep driving?
If the selector is trapped in Park, keep the vehicle parked and do not force the lever, which can damage the interlock. Use the vehicle’s owner manual for any emergency release procedure and address the fault before relying on the selector.
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.