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Tahoe / Yukon Service Manual

DTC B1A6C

Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC Descriptor DTC B1A6C Universal Serial Bus (USB) Circuit For symptom byte information, refer to Symptom Byte List. Circuit/System Description The surround vision camera system has a X20 Card Reader Receptacle located in the luggage compartment. The X20 Card Reader Receptacle interfaces with the K157 Video Processing Module via a USB cable. The X20 Card Reader Receptacle also receives fused battery voltage and ground from the K157 Video Processing Module . The K157 Video Processing Module uses the memory card as a mass storage device, similar to a USB storage device. Conditions for Running the DTC Ignition voltage is between 9–16 V. Conditions for Setting the DTC The rearview camera video circuit is open, shorted to voltage, or shorted to ground. Action Taken When the DTC Sets The Video Processing Control Module requests the instrument cluster to display “Service Surround Vision Camera”. The Video Processing Control Module will disable the recording. Conditions for Clearing the DTC A current DTC clears when the malfunction is no longer present. A history DTC clears when the control module ignition cycle counter reaches the reset threshold of 100, without a repeat of the malfunction. Diagnostic Aids USB cables must be fully connected to function properly. Ensure USB cables are properly connected at all components. Reference Information Schematic Reference Image Display Camera Schematics Connector End View Reference Master Electrical Component List Description and Operation Surround Vision Camera Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References for scan tool information Special Tools EL-50334-50  GM Infotainment Tester Kit Circuit/System Verification

  1. Ignition ON, Surround Vision Camera system ON.
  2. Verify the Surround Vision Camera images displays properly. ⇒ If Surround Vision Camera images do not display properly Refer to Surround Vision Camera System Malfunction ⇓ If Surround Vision Camera images displays properly
  3. Verify the Surround Vision Camera system plays recordings on the A22 Radio Control Module. ⇒ If Surround Vision Camera system displays NO SD CARD INSERTED 3.1. Ensure SD card is a Fat32 formatted Class 10 or higher branded HC SD memory card. ⇒ If SD card is a Fat32 formatted Class 10 or higher branded HC SD memory card Refer to Circuit/System Testing. ⇓ If SD card is not Fat32 formatted Class 10 or higher branded HC SD memory card Replace SD card with Fat32 formatted Class 10 or higher branded HC SD memory card and verify Surround Vision Camera system displays properly. ⇒ If Surround Vision Camera system does not display or play recordings properly Refer to Circuit/System Testing. ⇓ If Surround Vision Camera system displays and plays recordings properly
  4. Verify the Surround Vision Camera system records properly to an SD card. ⇒ If Surround Vision Camera system does not record properly 4.1. Verify a properly formatted SD card is inserted in X20 Card Reader Receptacle ⇒ If VIDEO PLAYER UNAVAILABLE or VIDEO FILE NOT SUPPORTED message displayed Format SD card ⇓ If formatted SD card is inserted Refer to Circuit/System Testing. ⇓ If Surround Vision Camera system records properly
  5. A fault is not currently present and may be an intermittent condition. Circuit/System Testing
  1. Ignition OFF, disconnect the X1 harness connector at the X20 Card Reader Receptacle .
  2. Test for less than 10 Ω between the ground circuit terminal 4 and ground. ⇒ If 10 Ω or greater 2.1. Ignition OFF. 2.2. Test for less than 2 Ω in the ground circuit end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, repair the open/high resistance in the ground connection. ⇓ If less than 10 Ω
  3. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground. ⇒ If the test lamp does not illuminate 3.1. Ignition OFF, remove the test lamp. 3.2. Test for less than 2 Ω in the B+ circuit end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇓ If the test lamp illuminates
  4. Connect the X1 harness connector at the X20 Card Reader Receptacle .
  5. Verify the USB cable is properly connected at all components and in-line connections, and there is no damage to the cable or connections. ⇒ If connection problems or cable damage is noted. Perform the appropriate repair or replacement to correct any issues. ⇓ If no connection problems or cable damage is noted.
  6. Connect the EL-50334-50  to the X20 Card Reader Receptacle connector X2 and the K157 Video Processing Module connector X5.
  7. Ignition ON, Surround Vision Camera system ON.
  8. Verify the card reader receptacle operates properly while operating the Surround Vision Camera system. ⇒ If memory card receptacle does not operate properly 8.1. Replace the X20 Card Reader Receptacle . 8.2. Verify the memory card receptacle operates properly while operating the Surround Vision Camera system. ⇒ If memory card receptacle does not operate properly Replace the K157 Video Processing Module . ⇓ If memory card receptacle operates properly All OK ⇓ If memory card receptacle operates properly
  9. Replace the USB harness. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Control Module References for control module replacement, programming, and setup.