P255C code meaning
PTO Speed Selector Sensor/Switch 2 Circuit Low
What P255C means
P255C means the input of PTO speed selector 2 reads lower than the controller's bottom limit, usually because the signal wire has a short to chassis ground or the switch is shorted inside. On designs where a grounded line is itself the command, as with the switch-to-ground inputs of Ram's 2017 VSIM, a short looks exactly like a permanently held preset 2 request; the controller can only tell the difference when the selector is resistor-coded or monitored with a diagnostic current. No manufacturer publishes P255C. P255D is the high-side fault on the same input, P254C the low fault on selector 1. Possible results are an engine that stays at the second working speed whenever PTO is active, or a PTO that the controller blocks.
P255C at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P255C
- Engine always runs at the second preset in PTO mode
- PTO blocked
Common causes of P255C
- Most likelySelector 2 wire shorted to chassis ground
- PossibleSelector 2 shorted internally
- Less likelyHarness pinched under a body mounting
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pto speed selector 2
What each part of P255C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 5C | The exact fault in that area. |
What to do next
- Note P255C and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P255C
What does P255C mean?
P255C means "PTO Speed Selector Sensor/Switch 2 Circuit Low". P255C means the input of PTO speed selector 2 reads lower than the controller's bottom limit, usually because the signal wire has a short to chassis ground or the switch is shorted inside. It is a generic code, so it means the same on every make.
Is it safe to drive with P255C?
P255C does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will P255C fail an emissions test?
P255C is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P255C to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P255C clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.