P0727 OBD II Trouble Code Engine Speed Input Circuit No Signal

How to diagnose, repair, and info on causes of a P0727 engine code which means the engine speed input signal is not detected. Also includes links to relevant forum topics on the code.

Symptoms of P0727 OBD II Trouble Code

  • Automatic transmissions may shift harshly (limp-in mode)
  • Transmission fails to shift or shifts erratically
  • Erratic or inoperative speedometer/odometer
  • Inoperative or incorrect tachometer
  • Transmission slippage or delayed engagement
  • Additional transmission input/output speed codes may be stored

Common Causes of P0727 OBD II Trouble Code

  • Open or shorted wiring and/or connectors in the engine speed input circuit
  • Excessive metal deposits on the magnetic tip of the sensor
  • Defective engine speed input sensor or transmission output speed sensor
  • Damaged or worn engine speed sensor reluctor ring
  • Mechanical transmission failure which results in transmission/clutch slippage

Severity of P0727 OBD II Trouble Code

A stored code P0727 should be rectified with urgency as severe transmission damage and/or drivability issues may result.