Circuit/System Verification

WARNING: This page is about a different car, the 2022 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.

Ignition ON/Vehicle In Service Mode.
Verify DTC U0073 - U007E is not set.
- If any of the DTCs are set
  Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Go to next step: If none of the DTCs are set
Verify DTC U0100 or U1611 is not set.
- If any of the DTCs are set
  Refer to DTC U0100-U02FF (Using Digital Multimeter) , or DTC U0100-U02FF (Using Network Communication Status) , or DTC U1611 to diagnose the K20 Engine Control Module first.
- Go to next step: If none of the DTCs are set
Verify DTC U2405 is not set.
- If the DTC is set
  Refer to Circuit/System Testing to diagnose the K56 Serial Data Gateway Control Module which is gating messages from K20 Engine Control Module on CAN 2 bus to K212 Gear Shift Control Module on CAN 3 bus.
- Go to next step: If the DTC is not set
A fault is currently not present and may be an intermittent condition.