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.

NOTE:

If stored only as a history DTC and not retrieved as a current DTC, do not perform the Serial Data Authentication Configuration procedure.

Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. It may take up to 10 min for all vehicle systems to power down.
Ignition ON/Vehicle In Service Mode.
Verify DTC U1983 is not set.
- If the DTC is set
1. Verify DTC U1961 is not set in the K56 Serial Data Gateway Module.
  - If DTC U1961 is set as a current DTC, replace the K56 Serial Data Gateway Module.
  - If DTC U1961 is set as a history DTC
  1. Clear DTCs in the K56 Serial Data Gateway Module and K20 Engine Control Module.
  2. Verify DTC U1983 and DTC U1961 are not set again.
    - If DTC U1983 is set again and DTC U1961 is not set, replace the K20 Engine Control Module.
    - If DTC U1983 and DTC U1961 are both set again, replace the K56 Serial Data Gateway Module.
    - Go to next step: If DTC U1983 and DTC U1961 are not set
  3. All OK.
  - Go to next step: If DTC U1961 is not set
2. Clear DTCs in the K20 Engine Control Module.
3. Verify DTC U1983 is not set again.
  - If the DTC is set, replace the K20 Engine Control Module.
  - Go to next step: If the DTC is not set
4. All OK.
- Go to next step: If the DTC is not set
Verify DTC U0073-U007E, U0100-U02FF, U1100-U12FF, U1600-U17FF, U1977, U1978, U2200-U23FF, or U2400-U25FF is not set.
- If any of the DTCs are set
  Refer to Diagnostic Trouble Code (DTC) List - Vehicle to diagnose those DTCs first.
- Go to next step: If none of the DTCs are set
Verify DTC U1982 is not set.
- If the DTC is set
1. Perform the Serial Data Authentication Configuration procedure in SPS. Refer to Serial Data Authentication Configuration .
2. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. It may take up to 10 min for all vehicle systems to power down.
3. Ignition ON/Vehicle In Service Mode.
4. Verify the DTC does not set.
  - If the DTC sets, replace the K56 Serial Data Gateway Module.
  - Go to next step: If the DTC does not set
5. All OK.
- Go to next step: If the DTC is not set
Verify DTC U1984 is not set.
- If the DTC is set along with DTCs U0400-U05FF, U1300-U14FF, or U2500-U25FF
1. Perform the Serial Data Authentication Configuration procedure in SPS. Refer to Serial Data Authentication Configuration .
2. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. It may take up to 10 min for all vehicle systems to power down.
3. Ignition ON/Vehicle In Service Mode.
4. Verify the DTC does not set.
  - If the DTC sets, program the control module that the majority of control modules set invalid data DTCs against. If the DTC resets, replace the control module that was just programmed.
  - Go to next step: If the DTC does not set
5. All OK.
- If the DTC is set without DTCs U0400-U05FF, U1300-U14FF, and U2500-U25FF
1. Perform the Serial Data Authentication Configuration procedure in SPS. Refer to Serial Data Authentication Configuration .
2. Ignition/Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. It may take up to 10 min for all vehicle systems to power down.
3. Ignition ON/Vehicle In Service Mode.
4. Verify the DTC does not set.
  - If the DTC sets, replace the K56 Serial Data Gateway Module. Perform the Serial Data Authentication Configuration procedure again. If the DTC resets, contact Technical Assistance Center for further instructions.
  - Go to next step: If the DTC does not set
5. All OK.
- Go to next step: If the DTC is not set
All OK