Circuit/System Verification

WARNING: This page is about a different car, the 2016 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

Verify no DTCs are present.
- If any DTCs are present
  Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- If no DTCs are present
Verify the K74 Human Machine Interface Control Module calibrations are current.
- If the K74 Human Machine Interface Control Module calibrations are not current
  Reprogram the K74 Human Machine Interface Control Module and re-evaluate the concern.
- If no update calibrations are available
Ignition On/Vehicle in Service Mode. Infotainment system ON.
NOTE: The MIT tool can be used to test either cellular phone or streaming audio functions. Refer to the tool instructions and perform the appropriate test(s) related to the customers concern in the following steps.
Verify the infotainment system successfully pairs with the MIT tool.
- If the infotainment system does not successfully pair with the MIT tool.
  Replace the K74 Human Machine Interface Control Module.
- If the infotainment system successfully pairs with the MIT tool.
Verify the infotainment system successfully completes the desired feature test using the MIT tool.
- If the feature test is not successful
  Replace the K74 Human Machine Interface Control Module.
- If the feature test is successful
All OK. Refer to Diagnostic Aids .