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Home >> Kia >> 2020 >> Optima Plug-In Hybrid EX >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Diagnosis (6 Of 6) (PHEV) >> DTC U0456-00: Invalid Data Received From Coolant Temperature Control Module >> Wiring Inspection >> Module Circuit Inspection
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Module Circuit Inspection

Power Circuit Inspection 

  1. Ignition "OFF"
  2. Refer to "ELECTRIC WATER PUMP (EWP) " and disconnect EEWP connector.
  3. Ignition "ON"
  4. Measure voltage between Pin No. 7 (Power) terminal of EEWP harness connector and chassis ground.
  5. Measure voltage between Pin No. 2 (ON/Start Input) terminal of EEWP harness connector and chassis ground.

    Specification:  B+

  6. Is measured value within specification?

    YES 

    • Go to "Ground Circuit Inspection" procedure below.

    NO 

Ground Circuit Inspection 

  1. Ignition "OFF"
  2. Disconnect Battery (-) terminal.
  3. Refer to "ELECTRIC WATER PUMP (EWP) " and disconnect EEWP connector.
  4. Measure resistance between Pin No. 6 (Ground) terminal of EEWP harness connector and chassis ground.

    Specification:  Approx. below 1Ω

  5. Is measured value within specification?

    YES 

    • Go to "Open in CAN Communication Line Inspection" procedure below.

    NO 

Open in CAN Communication Line Inspection 

  1. Ignition "OFF"
  2. Disconnect Battery (-) terminal.
  3. Disconnect PCM and EEWP connectors.
  4. Measure resistance between Pin No. 77 (P-CAN High) terminal of PCM and Pin No. 4 (P-CAN High) terminal of EEWP.
  5. Measure resistance between Pin No. 60 (P-CAN Low) terminal of PCM and Pin No. 5 (P-CAN Low) terminal of EEWP.

    Specification:  Approx. below 1Ω

  6. Is measured value within specification?

    YES 

    NO