There may be several DTCs set and ADAS-related messages displayed on the Driver Information Center related to the B174W Front View Camera Module (ACP2) (Fig. 14) on some 2024-2026 Chevrolet, Buick, GMC and Cadillac models. DTCs may include:
- U1615/U1616 – Lost Communication with ACP2 on CAN Bus 2 or CAN Bus 8
- U197A – Ethernet Time Synchronization Signal Invalid (set by ACP2)
- U0499 – Invalid Data Received from Telematics Control Platform Module (set by ACP2)
- U0235 – Lost Communication with Forward LRR sensor (set by ACP2)
- B1A05 – ACP2 MCU Missing Calibration (set by ACP2)
- U3000 – Control Module set by ACP2 or other ECUs
Fig. 14
The latest Engineering analysis and field reviews have identified that many B174W Front View Camera replacements are the result of incomplete diagnostics or non-camera root causes, including:
- Vehicle power or 12-volt system concerns, including low battery state-of-charge and related DTCs (e.g., P0562, U3003-16)
- Serial data, CAN bus, or Ethernet issues involving the K56 Serial Data Gateway Module and other ECUs (engine, transmission, EBCM, steering, radar sensors, etc.).
- Non-GM windshield glass or incorrect windshield installation (improper bracket alignment, incorrect glass, applied tints, or other alterations) that affect camera performance and calibration.
- Improper ACP2 seating or bracket installation at the windshield.
- Software anomalies or calibration issues requiring reprogramming and the Front View Camera – Windshield Learn procedure.
- Other ECUs setting DTC U3000 or related DTCs where the root cause is not the Front Camera Module.
As a result, replacing the B174W Front View Camera Module without following the complete diagnostic procedures in the appropriate Service Information often does not resolve the concern and contributes to unnecessary part usage. In some cases, the Front View Camera may have already been replaced.
Diagnostic Tips
There are several diagnostic steps to follow to determine the root cause of a Front View Camera condition. Refer to #PIT6503 for additional information.
These steps include checking for prior camera replacement, duplicating the condition, identifying any specific conditions when the concern occurs, verifying the windshield is GM original equipment glass, inspecting the mounting of the ACP2 module, checking communication with the ACP2 using a wired connection, addressing any 12-volt battery issues and determining the cause of any other DTCs.
Parts Restriction
Once all diagnostic results are completed, if it is determined that the B174W Front View Camera Module should be replaced, contact the Product Quality Center (PQC) to request authorization. A summary of the condition, recorded DTCs and the SI procedures followed will be required.
After replacement, it will be necessary to reprogram the ACP2 and perform the Front View Camera – Windshield Learn procedure.
For more details, including diagnostic steps and part numbers, refer to #PIT6503.
– Thanks to Brett Mulvaney
