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Home >> Kia >> 2016 >> Cadenza Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (3 Of 3) >> DTC P0685: ECM/PCM Power Relay Control Circuit/Open >> DTC Information >> DTC Detecting Condition
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DTC Information: DTC Detecting Condition

Item Detecting Condition Possible cause
DTC Strategy
  • Detects a short to ground, short to battery (+), or open control circuit on the main relay
  1. Poor Connection
  2. Open or short in control circuit
  3. Faulty Main Relay
  4. Faulty PCM
Enable Conditions
  • Engine Running
  • Ignition Voltage between 11V and 16V
Threshold value
  • Open or Short in circuit
Diagnosis Time
  • Continuous (More than 5 sec. failure for every 10 sec. tested)
MIL On Condition
  • DTC only (NO MIL ON)

* If Main relay has a fault (ex. when the engine is running), the DTC's, P0638/P0685/P1295/P2106, can set at the same time.