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CAN Communication Line Check

WARNING: This page is about a different car, the 2013 Kia Sportage and 2012 Kia Sportage. However, it is still accessible from the selected car via links, so may be relevant.

■ CAN communication circuit inspection (ESC↔ 4WD ECU) 

  1. Ignition "OFF"
  2. Disconnect 4WD ECU connector and ESC connector.
  3. Measure the resistance between CAN-HIGH terminal of 4WD ECU harness connector and CAN-HIGH terminal of ESC harness connector.
  4. Measure the resistance between CAN-LOW terminal of 4WD ECU harness connector and CAN-LOW terminal of ESC harness connector.

    Specification:  below 1Ω

    Fig 1: Measuring Resistance Between CAN-LOW/HIGH Terminals Of 4WD ECU & CAN-LOW/HIGH Terminals Of ESC Harness Connector
    G07422943Courtesy of KIA MOTORS AMERICA, INC.
    Fig 2: TPMS, Data Link Connector, ABS & PCM Connector End Views
    G07422944Courtesy of KIA MOTORS AMERICA, INC.
  5. Is the measured resistance within specification?

    YES 

    • Check 4WD ECU connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.

    NO 

    • If the measured value is ∞ Ω, repair or replace the open in CAN High/CAN Low circuit. And then, go to "VERIFICATION OF VEHICLE REPAIR " procedure.

■ Check short to ground in CAN communication line 

  1. IG key "OFF".
  2. Measure resistance between CAN high terminal (# 3) of diagnostic connector and chassis ground.
  3. Measure resistance between CAN low terminal (# 11) of diagnostic connector and chassis ground.

    Specification:  ∞ Ω

    Fig 3: Measuring Resistance Between CAN Low/High Terminals (# 11)/(# 3) Of Diagnostic Connector & Chassis Ground
    G07422945Courtesy of KIA MOTORS AMERICA, INC.
    Fig 4: TPMS, Data Link Connector, ABS & PCM Connector End Views
    G07422946Courtesy of KIA MOTORS AMERICA, INC.
  4. Is the measured value within specification?

    YES 

    • Check PCM, 4WD ECU and ESC ECM connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.

    NO 

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