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Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
  1. Ignition OFF, disconnect the harness connector at the S48E multifunction switch.
  2. Ignition OFF and all vehicle systems OFF, test for less than 5 Ω between ground circuit terminal 2 of the harness connector and ground.
    NOTE: It may take up to 2 minutes for all vehicle systems to power down.
    • If greater than the specified value, test the ground circuit for an open/high resistance and repair as necessary.
  3. Ignition ON, test for 4.8-5.2 V between 5 V reference circuit terminal 6 of the harness connector and ground.
    • If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
    • If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  4. Ignition ON, test for 0.050-0.250 V between signal circuit terminal 5 of the harness connector and ground.
    • If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K20 ECM.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
  5. If all circuits test normal, test or replace the S48E multifunction switch.
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