P0722: Output Speed Sensor Circuit No Signal

What it means

TCM detects no output shaft speed signal while the vehicle is moving. Triggers shift abnormalities, speedometer issues, and limp-home mode.

At a glance

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

How it works

The output speed sensor measures transmission output-shaft rotation for the control module. P0722 sets when the vehicle is moving but the module receives no output-speed signal, which can disrupt shift control and may also affect vehicle-speed information.

Common causes

Most likely first.

1. Output speed sensor failed
2. Wiring or connector fault

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. Check freeze-frame data and live output-speed data to confirm the signal is absent while the vehicle is moving.
2. Compare the scan tool's vehicle speed and output speed readings, and check for related speed-sensor codes that may point to a shared issue.
3. Inspect the output speed sensor connector and harness for disconnection, corrosion, fluid intrusion, or broken and rubbed-through wires.
4. Check that the output speed sensor is securely mounted and that its wiring has not been damaged near the transmission.
5. Use the wiring diagram to test sensor power or reference, ground, wiring continuity, and signal as applicable against the manufacturer's specification.

Common fixes

• Reconnect or clean the output speed sensor connector.
• Repair open, shorted, or damaged output speed sensor wiring.
• Secure a loose sensor mounting if applicable.
• Replace the output speed sensor if the circuit is sound but it produces no signal.

Can I keep driving?

Avoid unnecessary driving because missing output-speed data can cause erratic shifts or limp mode. If the transmission cannot shift safely or predictably, stop and arrange diagnosis.