P0952: Auto Shift Manual Control Circuit Low

What it means

The auto-shift manual control circuit reports a low condition. Manual mode shift requests cannot be reliably interpreted.

At a glance

• Usually lights the check-engine light

How it works

The auto-shift manual control circuit carries manual gear requests to the control module. P0952 sets when that input stays electrically low, as can happen when the signal wire is shorted to ground, the switch remains closed, or corrosion disrupts the connector contact.

Common causes

Most likely first.

1. Wire shorted to ground
2. Switch stuck closed
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. Save freeze-frame data and check live data to confirm the manual control input stays low while the control is released and operated.
2. Inspect the switch connector and harness for corrosion, damaged insulation, trapped wiring, or a pin contacting ground.
3. Check whether the switch is stuck closed by monitoring its signal as the control is moved through its positions.
4. With the wiring diagram, test the signal circuit for a short to ground and inspect connector pins for poor contact.
5. If the circuit is not grounded and the switch changes correctly, check the module input using the manufacturer's diagnostic information.

Common fixes

• Clean or repair corroded manual control connector pins.
• Repair a signal wire shorted to ground.
• Replace a switch that remains closed when released.
• Repair a confirmed module input fault.

Can I keep driving?

Manual gear requests may be ignored or interpreted incorrectly, while automatic shifting may remain available. Avoid relying on manual mode and drive gently if the transmission also shifts harshly or enters limp mode.