OBD-II code · Powertrain (generic)
P0720 Output Speed Sensor Circuit Malfunction
The transmission output speed sensor signal is missing or implausible. The TCM uses this signal together with input speed to determine actual gear ratio; many vehicles also use it as a backup vehicle speed signal for the cluster and ECU.
Is it safe to drive with P0720?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyOutput speed sensor failed
- PossibleWiring 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
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1.5–6 h
- Emissions test
- Usually unaffected
- Parts involved
- Transmission Output Speed Sensor, Transmission Output Speed Sensor Wiring
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.