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Circuit/System Testing

WARNING: This page is about a different car, the 2011 Chevrolet Volt. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the S78 Turn signal/Multi-Function Switch harness connector. Test for less than 5 Ω between the ground circuit terminal 6 and ground.
    • If greater then the specified value, test the ground circuit for an open/high resistance.
  2. Connect the S78 Turn signal/Multi-Function Switch harness connector.
  3. Disconnect the X1 harness connector at the K9 Body Control Module.
  4. Connect a test lamp between B+ and the signal circuit terminal 16.
  5. Turn the headlamp switch between the low beam and OFF position. The test lamp should turn ON and OFF as the switch is cycled.
    • If the test lamp is always OFF, test the signal circuit for a short to voltage or an open/high resistance. If the circuit test normal, replace the S78 Turn signal/Multi-Function Switch.
    • If the test lamp is always ON, test the signal circuit for a short to ground. If the circuit test normal, replace the S78 Turn signal/Multi-Function Switch.
  6. If all circuits test normal, replace the K9 Body Control Module.
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