Severity: Fix right away. Driving risks expensive damage or a breakdown.
The computer is getting no usable signal from the sensor that measures how fast the transmission output shaft is turning, which also feeds the speedometer.
Check the wiring and connector, clean the sensor, and replace it if it gives no signal.
The speedometer may not work and the transmission may shift oddly or go into limp mode. Get it checked soon.
Avoid driving until it is checked — towing is the safer choice. The speedometer may not work and the transmission may shift oddly or go into limp mode. Get it checked soon.
The most common causes are: Failed output speed sensor; Damaged wiring or connector; Metal debris on the sensor; Damaged tone ring. A scan tool and a visual check of the parts above is where a technician starts.
Check the wiring and connector, clean the sensor, and replace it if it gives no signal.
