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Home >> GMC >> 2019 >> Terrain SL >> Repair and Diagnosis >> External Pages >> Different car >> Section 211 (Driver Assistance Systems) >> Diagnostic Information and Procedures >> DTC B1B4A >> Circuit/System Verification
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Circuit/System Verification

WARNING: This page is about a different car, the 2021 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify no other DTCs related to the B174W Frontview Camera - Windshield are set.
    • Go to next step: If no other DTCs are set 
  2. Verify the area in front of the B174W Front View Camera - Windshield is clean, unobstructed, and damage-free
    • If not clean, unobstructed, and damage-free 

      Repair or replace components as necessary.

    • Go to next step: If clean, unobstructed, and damage-free 
  3. Verify the B174W Front View Camera - Windshield is properly mounted and secured with no damage.
    • If not properly mounted and secured or damage is present 

      Repair or replace components as necessary.

    • Go to next step: If properly mounted and secured or damage is present 
  4. Clear DTCs and operate the vehicle in the conditions that the customer experienced.
  5. Verify DTC B1B4A does not set.
    • If DTC B1B4A is set 
    1. Replace the B174W Frontview Camera - Windshield.
    2. Clear DTCs and operate the vehicle.
    3. Verify the DTC does not reset.
      • If the DTC resets, replace the K124 Image Processing Module
      • Go to next step: If the DTC does not reset

        Go to next step: All OK.

    • Go to next step: If DTC B1B4A is not set 
  6. All OK. A fault is currently not present and may be an intermittent condition.
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