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Home >> Kia >> 2017 >> Optima Plug-In Hybrid EX >> Repair and Diagnosis >> Transmission >> Automatic Trans >> Automatic Transaxle System Diagnosis (PHEV) >> DTC P0721: Output Speed Sensor Circuit Range/Performance >> DTC Information >> DTC Detecting Condition
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DTC Information: DTC Detecting Condition

Item Detecting Condition Possible Cause
DTC Strategy
  • Voltage Monitoring
  1. Poor Connector Connection
  2. Faulty output Speed Sensor Circuit
  3. Faulty output Speed Sensor
Enable Conditions
  • Battery voltage is above 10V
  • Vehicle Speed higher than 50km/h (31mph)
  • Lever Position in "D" or "Sports" (Forward Gear)
Threshold value
  • Vehicle speed equivalent to output speed is less then vehicle speed * 0.5 or higher than vehicle speed * 1.5 (ex. Less than 25km/h (15mph) or higher than 75km/h (46mph) when vehicle speed is 50km/h (31mph)
Fail safe
  • Limp home mode (4th gear hold, manual shift from 2nd to 4th gear is allowed)
Detecting Time
  • 5s
MIL ON Condition
  • 2 Driving Cycles