Error Code P0930 is defined as Gear Shift Lock Solenoid Circuit “A” Low. This is a generic trouble code, meaning it applies to all vehicles equipped with the OBD-II system, especially those made since 1996 up to the present. Of course, specifications on the definition, troubleshooting, and repairs vary from one make and model to another.

The problem relates to the automatic transmission and the shift lock solenoid. The latter keeps the gear shifter from being moved out of the park without pressing down the brake pedal.

This code means there is a low voltage problem in the gear shift lock solenoid. When this happens, the vehicle’s powertrain control module (PCM) will not recognize the brake pedal when it is pressed. As a result, the gear shift lock solenoid works in combination with the brake light switch.

Common Symptoms

  • Gear unable to shift out of park
  • Check engine light activated

Fortunately, most modern vehicles with automatic transmission come with a built-in fail-safe that can be accessed via screwdriver.

Possible Causes

This problem is rarely caused by one problem, but it mainly includes:

  • Defective brake light switch
  • Defective gear shift lock solenoid
  • Low battery voltage

How to Check

The most common fix for this problem is bypassing the gear shift solenoid through an access panel usually found near the shifter.

Then, the solenoid must be tested for continuity. If it shows problems, then it must be replaced.

How to Fix

  • Replacement of the defective gear shift lock solenoid
  • Replacement of brake pedal switch

Though rare, low battery voltage can also cause this code.

Since this code keeps the gear from shifting out of park, it immobilizes the vehicle. Thus, though this does not cause serious damage, it is an urgent situation that needs fixing as soon as possible.