Powertrain, generic (extended)

P255C PTO Speed Selector Sensor/Switch 2 Circuit Low

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

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.

Likely causes

Selector 2 wire shorted to chassis ground
Selector 2 shorted internally
Harness pinched under a body mounting

Symptoms

  • Engine always runs at the second preset in PTO mode
  • PTO blocked

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–300
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

pto speed selector 2

Related codes

P255AP255BP255DP255EP254C

References: law.cornell.edu, http:.