Can’t shift out of park, shift lock release not working
Car makers starting installing shift interlock safety features in the 1990’s to prevent drivers from shifting out of park without first turning the key. Then in 2010 all vehicles were required to install a shift interlock mechanism that used a shift lock release to prevent drivers from shifting out of park without first applying the brake. When the shift lock release fails, you can’t shift out of park.
How a shift interlock and shift lock release works
Car makers install a shift lock that latches when the shifter is placed in the park position. To unlock the shift lock, the driver applies the brake pedal. That activates the brake light switch which then applies power to the shift lock release solenoid, also called the shifter interlock solenoid. The shift lock release solenoid moves the latching pin out of the way so the driver can shift out of park.
What goes wrong with the shift lock release?
The shift lock mechanism can fail in several ways; car battery is dead so no power flows to shift lock release solenoid, brake pedal switch or wiring has failed, prevent power from reaching the solenoid or the solenoid itself has failed.
I’ll give you some diagnostic tips below, but if you just want to start the vehicle and get going now, here’s how to override the shift lock mechanism.
All car makers provide an override procedure. It’s shown in your owner’s manual. Depending on whether your shifter is located on the steering column or the console, you’ll usually have a plastic disc covering the shift lock override. Remove the plastic disc and follow this procedure:
1) Apply your parking brake
2) Apply the brake pedal
4) Remove the screwdriver or nail file from the slot.
5) With your foot still on the brake pedal, start the engine.
6) With your foot still on the brake pedal, release the parking brake and move the shifter to the D position.
7) Repair the inoperative shift lock release mechanism as soon as possible. This bypass procedure is designed for temporary use only.
Fix an inoperative shift lock release mechanism
1) Check your brake lights. Have a friend apply the brakes and see if the brake lights are on. If so, that proves the fuse is good and the brake light switch is working. If the brake lights don’t come on, check the fuse to that circuit (consult your owner’s manual to find the fuse and it’s location). If the fuse is good, obtain a wiring diagram and test for power on the wire going to the shift lock release solenoid when the brake pedal is applied.
2) Inspect the shift lock release solenoid. If you have power coming to the solenoid when the brake pedal is applied, check for good ground at the solenoid. If that checks out, look for an evidence of binding that might cause the locking pin to bind. If everything appears normal, replace the solenoid and re-test.
© Rick MuscoplatPosted on by Rick Muscoplat