Generic fault code
P255D — PTO speed selector sensor/switch 2, circuit: signal high
The control unit stores code P255D when it detects this fault: “PTO speed selector sensor/switch 2, circuit: signal high”.
Indicative severity: MediumSpeed, idle and auxiliary inputs
Reviewed by Daniel Morales, founder of Reprorace SL, on
What does code P255D mean?
The vehicle speed sensors and idle control, the speed the engine turns at when you are not accelerating.
- System
- P · Powertrain
- Area
- Speed, idle and auxiliary inputs · Car system: Fuel and air
- Type
- Generic (SAE J2012 / ISO 15031-6): the same meaning on every make
- Indicative severity
- Medium. Diagnose soon: it may raise emissions or consumption, or trigger limp-home mode.
What usually causes code P255D?
- Short circuit to battery or another voltage
- Loose or corroded connector, backed-out terminals
- Poor module supply or ground (fuse, relay, battery)
The most likely causes come first. Only a check on the car confirms which one is yours.
What are the symptoms of code P255D?
- Speedometer or cruise control not working properly
- Idle too high, too low or unstable
- Odd shifts on automatics, or ABS and ESP lights
These are the usual symptoms of this kind of fault: not all of them always appear, and sometimes you notice nothing.
Can I keep driving with code P255D?
With care, and not for long. You can take the car to a workshop, ideally without long trips or heavy loads, and without putting it off: fuel use or emissions may rise and the car may go into limp-home mode (less power). If the light flashes, a red warning light comes on, the temperature rises or you notice a loss of power, noises or smoke, stop as soon as it is safe.
This is guidance only: only someone who checks the car can say whether it is safe to drive.
An indicative description of the code's generic meaning. Each manufacturer may give it a different meaning, conditions or tests: always follow its service information and your workshop's advice.
What you can do yourself
For this kind of fault
Note whether the fault appears with something specific, such as braking, switching on the air conditioning or turning the wheel: it helps the workshop find the input at fault.
Read the code and keep the report: with an ECO-LITE in the OBD socket you see it on your phone or computer, with the data captured when the fault happened.
Look for anything obvious: a loose connector, a disconnected hose, a fuel cap not closed properly or a low fluid level. Do not take apart anything you do not know.
Clear the code only after writing it down or after the repair. Clearing turns the light off, but it also deletes the freeze-frame data and the readiness monitors used at the inspection.
Drive normally for a few days and read the codes again. If the code comes back, the fault is still there: book the workshop and bring the report.
Read your car's fault codes on your phone
With an ECO-LITE in the OBD socket you see the codes in your account, with the data captured when the fault happened, and your workshop can check them remotely, always with your permission.
Related codes
- P254APTO speed selector sensor/switch 1, circuit open
- P254BPTO speed selector sensor/switch 1: range/performance
- P254CPTO speed selector sensor/switch 1, circuit: signal low
- P2550Torque management request input signal B: signal low
- P2551Torque management request input signal B: signal high
- P255EPTO speed selector sensor/switch 2, circuit: intermittent/erratic
In the glossary
Read more: Remote OBD diagnostics: what it is, how it works and what it can't do