OBD-II trouble code
P0930: Gear Shift Lock Solenoid Control Circuit Low
A low-voltage fault on the shift lock solenoid circuit. The single most useful thing to establish first is whether the key also refuses to come out — because on most vehicles that is a different mechanism entirely, and it changes what you are looking for.
Quick facts
- System
- Powertrain
- Category
- Transmission / Shift Control
- Severity
- Medium severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $60 – $620
- DIY difficulty
- Intermediate DIY
What does P0930 mean?
P0930 is stored when the module driving the shift lock solenoid sees the circuit sitting lower than it should. In practice that usually means the drive wire has found a path to ground it was not supposed to have, or the solenoid winding has partially shorted internally, or a connector is passing current where it should not. The lock itself is the small device in the base of the selector assembly that stops the lever leaving Park until the ignition is on and the brake pedal is pressed.
Before anything else, separate two symptoms that owners describe interchangeably and that most parts catalogues do not distinguish clearly. A vehicle that will not come out of Park has a shift lock problem. A vehicle whose key will not come out of the ignition barrel has a key interlock problem — and on the majority of vehicles with a conventional key, that is a second, separate solenoid or a mechanical cable acting on the lock cylinder, not the device this code names. The two are wired into the same logic and often share a fuse, so they fail together often enough to blur the picture, but they are different parts in different places at different prices. If only the lever is stuck, work on the console. If only the key is stuck, the console solenoid is probably innocent. If both are stuck at once, stop chasing solenoids and go and look at the shared supply, because one fault upstream is a far more economical explanation than two failed devices.
The second thing worth understanding is why a low circuit is awkward to catch on this particular component. The shift lock solenoid is not a device that holds a state for minutes at a time like the shift and clutch actuators elsewhere in this range of codes. It is energised for the moment the driver presses the brake and asks for a gear, and then it is switched off again. Its whole working life is measured in fractions of a second at a time. That has a direct consequence for testing: a meter clipped across the circuit with the ignition on and nobody touching the brake pedal is measuring the circuit at rest, which is exactly the condition in which a drive-side short may look like nothing at all. The measurement that matters is taken during the pull-in, and a meter that averages over half a second will smooth the event into invisibility. Scope it, or use a scan tool's actuator command so the pulse can be held long enough to see.
One genuinely common cause deserves naming because it is cheap. Chafed insulation where the selector harness passes under or through the console frame lets the drive wire touch the metalwork of the assembly, which is grounded. That produces a textbook low circuit, is invisible with the trim in place, and is repaired with a length of tape rather than a part.
Common causes
- Shift lock solenoid drive wire shorted to ground or to chassis metal
- Chafed insulation where the selector harness passes through the console frame
- Partially shorted solenoid winding drawing more current than specified
- Corroded or water-damaged connector at the base of the selector assembly
- Moisture ingress into the console from a spill or a leaking screen surround
- Pinched harness after console or trim removal for other work
- Failed driver circuit inside the control module
- Incorrect or aftermarket solenoid with the wrong coil resistance fitted
- Damaged wiring after aftermarket alarm, remote start or stereo installation
- Ground fault in a shared circuit that also feeds the key interlock
Symptoms
- Selector lever will not move out of Park with the brake pressed
- Warning lamp with a transmission or shift interlock message
- Solenoid buzzing continuously or getting warm to the touch
- Blown fuse on the circuit shared with the interlock system
- Key also refusing to release from the barrel, pointing at a shared supply
- Fault appearing shortly after console, stereo or alarm work
- Lock releasing only when the manual override is used
- No click at all from the console when the brake is pressed
- Transmission behaving entirely normally once a gear is selected
- Fault present constantly rather than intermittently
Diagnostic steps
- 1.Establish first whether the key releases normally, because a key that is also stuck points at a shared supply rather than at the console solenoid.
- 2.Check the fuse feeding the interlock circuit before opening anything, since a short to ground frequently takes it out.
- 3.Command the solenoid with a scan tool so the pulse can be held, rather than trying to catch a brake-pedal press with a meter.
- 4.Scope the drive circuit during the pull-in — a meter averaging over a fraction of a second will hide the event entirely.
- 5.Disconnect the solenoid and check whether the low reading persists, which separates a shorted winding from a shorted wire.
- 6.Measure solenoid coil resistance and compare against specification, as a partially shorted winding reads low and draws high.
- 7.Remove the console trim and inspect the harness where it passes through or under the selector frame for chafe against grounded metalwork.
- 8.Inspect the selector connector for green corrosion, water staining or crushed pins.
- 9.Review any recent electrical accessory installation, since interlock circuits are a common tapping point for remote start systems.
- 10.Only condemn the control module once the wiring and solenoid have both been cleared, because a drive-side short damages module outputs and may have been the original fault.
Repair cost
$60 – $620
Diagnosis is $60 to $180 and should include console trim removal, because the answer is often a chafed wire that cannot be seen with the trim fitted. Repairing a shorted or chafed harness section is $80 to $260. A shift lock solenoid supplied as a separate part is $110 to $400 fitted; where the manufacturer sells only the complete selector assembly, $260 to $620. If the key interlock is also faulty, price that separately — it is a different component and lumping the two together produces an estimate that is wrong in both directions.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with shift interlock (shift lock) solenoid replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an intermediate DIY job. It usually involves diagnostic steps, specialty parts, and some careful work in tight spaces. If you have the tools and a service manual or trustworthy video for your specific vehicle, it is achievable in a weekend. Otherwise, a competent independent shop will be faster.