P0913: Gate Select Actuator Circuit High

What it means

The gate select actuator circuit reports a high fault. Gate selection actuation is impaired. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.

At a glance

• Usually lights the check-engine light
• The engine or gearbox may go into limp mode

How it works

The gate select actuator moves the transmission mechanism between its shift gates, and the transmission control module (TCM) monitors the actuator circuit while commanding movement. P0913 sets when that circuit reads higher than expected, which can happen if its control wire is shorted to battery voltage, the actuator coil is open, or a connector has poor contact.

Common causes

Most likely first.

1. Control wire shorted to B+
2. Open coil
3. Connector pins corroded - high contact resistance

Symptoms

• Check engine or transmission warning light on
• Harsh, delayed, or missing shifts
• Possible limp mode (locked in one gear)
• Slipping or shuddering during gear changes

How to diagnose it

1. Record freeze-frame data and scan transmission live data for the commanded gate, actuator status, and circuit fault conditions to see when the high reading occurs.
2. Inspect the gate select actuator connector and harness for chafing, water intrusion, pushed-back pins, corrosion, or a wire contacting a power feed.
3. With the wiring diagram, check the gate select control wire for an unintended connection to battery positive and inspect connector continuity while gently moving the harness.
4. Measure the actuator coil for an open circuit and check its connector contacts against the manufacturer's specification.
5. If the wiring and coil pass, use scan-tool actuator commands to compare commanded and reported gate movement, then check for a mechanical obstruction.

Common fixes

• Repair chafed or pinched gate select actuator wiring that is shorted to power.
• Clean or repair corroded, wet, or pushed-back connector terminals and restore the seal.
• Replace the gate select actuator if its coil is open.
• Repair a binding gate mechanism if the actuator and circuit test correctly.

Can I keep driving?

Avoid driving if shifts are missing, harsh, slipping, or the transmission is stuck in one gear; arrange recovery if control is unpredictable. Continued use can worsen transmission damage, and limp mode may limit speed or available gears.