Gear Shift Foward Actuator Circuit High
The transmission's forward gear shift actuator is receiving too much electrical voltage, like a light switch getting too much power. The ECU detected the circuit voltage is higher than expected, preventing proper gear engagement.
The ECM monitors the voltage signal from the gear shift forward actuator solenoid circuit. It expects a specific voltage range during activation and de-activation cycles. When voltage exceeds the high threshold, the ECU identifies a circuit fault and triggers the code.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Actuator Circuit Voltage | 0.5V - 4.5V (varies by manufacturer) | Above 4.8V or shorted to power |
| Solenoid Current Draw | 0.5A - 2.0A | Excessive current or open circuit detected |
Code P0923 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0923 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.