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Tahoe / Yukon Service Manual

DTC B197D

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 No Environment Identifier Received from Restraints Control Module For symptom byte information, refer to Symptom Byte List. Circuit/System Description The Restraints Control Module sends the BCM a message telling the BCM that the correct Restraints Control Module is present. The message is sent and verified on every cycle of the key. If the BCM receives an incorrect response or no response at all, vehicle starting is disabled. Conditions for Running the DTC The vehicle is switched from OFF to RUN or propulsion. Conditions for Setting the DTC The BCM receives an incorrect response or no response at all for at least 10 seconds of the vehicle switched to RUN or propulsion. Action Taken When the DTC Sets Vehicle starting will be disabled if two or more modules set the No Environment Identifier Received DTC. Conditions for Clearing the DTC A current DTC will be cleared when the module sends the correct message. A history DTC will clear after 40 ignition cycles in which the correct message is sent. Reference Information Schematic Reference Immobilizer Schematics Connector End View Reference Master Electrical Component List Description and Operation Immobilizer 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 Circuit/System Verification

  1. Perform the Programming and Setup procedure for the K36 Restraints Control Module.
  2. Verify the DTC does not set after programming. ⇒ If the DTC sets after programming Replace the K36 Restraints Control Module. ⇓ If the DTC does not set after programming
  1. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Control Module References for module replacement, programming, and setup.