Circuit/System Verification

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

NOTE:

If the green LED is off with the ignition ON and the LED functions correctly when commanded with the scan tool, contact the OnStar Center to confirm the vehicle has a current subscription.

Ignition ON.
Verify that the green LED turns ON and OFF when commanding the K73 telematics communication interface control module green indicator ON and OFF with a scan tool.
- If the green LED does not turn ON and OFF
  Refer to Circuit/System Testing - Green LED Test
- If the green LED turns ON and OFF
Verify that the red LED turns ON and OFF when commanding the K73 telematics communication interface control module red indicator ON and OFF with a scan tool.
- If the red LED does not turn ON and OFF
  Refer to Circuit/System Testing - Red LED Test
- If the red LED turns ON and OFF
All OK.