P0920 critical

Gear Shift Forward Actuator Circuit Open

The P0920 code means the vehicle's onboard diagnostic system has detected: Gear Shift Forward Actuator Circuit Open. This is a critical severity code.

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Keep driving?
No -- stop driving
DIY difficulty
hard
Estimated cost
$300 - $1,500 (parts and labor)
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Common Symptoms

  • Check Engine Light illuminated
  • Transmission cannot shift to higher gears
  • Vehicle stuck in current gear
  • No upshift response from transmission

Probable Causes (Ranked by Likelihood)

  • Failed forward shift actuator motor Very High
  • Open circuit in forward actuator wiring High
  • Disconnected actuator connector Moderate
  • TCM shift output driver failure Low

Step-by-Step Diagnostic Procedure

  1. Check the forward shift actuator connector

  2. Measure actuator motor resistance

  3. Test wiring continuity from TCM to actuator

  4. Command the forward actuator with a bidirectional scan tool

Frequently Asked Questions

What is the forward shift actuator?

In automated manual transmissions, the forward shift actuator pushes the shift mechanism forward within the selected gate to engage a specific gear. It works in conjunction with the gate select and reverse actuators.

Will the car move at all with P0920?

The car may remain in whatever gear it was last in, but it cannot upshift. This makes it dangerous for driving and the vehicle should be towed.

Can the actuator be repaired?

Most actuators must be replaced as a unit. After replacement, a full calibration procedure is required.

Sources

This page is built from documented references. Verify against your own service info before repair work.

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