2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 240
Data Link Communications Description and Operation (See: Powertrain Management/Computers and Control Systems/Information
Bus/Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool References
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
Verify DTC B101E is not set.
If the DTC is set, program the control module. If the DTC resets, replace the control module.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for control module replacement, setup, and programming
B127C
DTC B1277, B127C, or B127D
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provide an overview of each diagnostic category.
DTC Descriptors
DTC B1277 01
- Microphone 1 (LF) Input Signal Circuit Short to Battery
DTC B1277 02
- Microphone 1 (LF) Input Signal Circuit Short to Ground
DTC B1277 04
- Microphone 1 (LF) Input Signal Circuit Open
DTC B1277 1A
- Microphone 1 (LF) Input Signal Circuit Bias Level Out of Range
DTC B127C 01
- Microphone 2 (RF) Input Signal Circuit Short to Battery
DTC B127C 02
- Microphone 2 (RF) Input Signal Circuit Short to Ground
DTC B127C 04
- Microphone 2 (RF) Input Signal Circuit Open
DTC B127C 1A
- Microphone 2 (RF) Input Signal Circuit Bias Level Out of Range
