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Circuit/System Testing

WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the B24 cellular phone microphone.
  2. Test for less than 10 Ω between the low reference circuit terminal A and ground.
    • If greater than the specified range, test the circuit for an open/high resistance.
  3. Ignition ON, test for 9.5-10.5 V between the signal circuit terminal B and ground.
    • If less than the specified range, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K73 telematics communication interface control module.
    • If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the K73 telematics communication interface control module.
  4. If all circuit test normal, replace the B24 cellular phone microphone.