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Tahoe / Yukon Service Manual

DTC B1575

Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions DTC Descriptor DTC B1575 Rear Closure ON/OFF Switch Signal Circuit Symptom Byte Information: Symptom Byte List Circuit/System Description For an overview of the component/system, refer to: Liftgate Description and Operation

Component Description
S45 Liftgate Control Switch Each function has its own switch. The switches are connected to a resistor ladder so that a specific resistance is generated for each switch.
A103 Roof Console The control module also reads various switches and sensors and makes their values available via serial data.

Conditions for Running the DTC Ignition » On / Vehicle » In Service Mode Conditions for Setting the DTC B1575 11 Signal — Liftgate Mode Switch Circuit = Short to Ground — For greater than 60 s B1575 15 Signal — Liftgate Mode Switch Circuit = Circuit Short To Battery or Open — For greater than 30 s Actions Taken When the DTC Sets Power Liftgate (TB5) » 3/4 & Manual = Disabled Conditions for Clearing the DTC A current DTC will clear when the diagnostic runs and passes. A history DTC will clear after 50 consecutive malfunction-free ignition cycles. Reference Information Liftgate Schematics Connector End View Reference Master Electrical Component List Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References Circuit/System Verification

  1. Verify the liftgate will perform the power open function when pressing the S45 Liftgate Control Switch. ⇒ If the liftgate does not power open Replace the component: A103 Roof Console . ⇓ If the liftgate does power open
  2. Set the S45B Liftgate Control Switch-Interior to the ¾ mode.
  3. Command the power liftgate to open by pressing the S45 Liftgate Control Switch. Verify the liftgate performs the power open function and stops at the garage mode position. ⇒ If the liftgate performs the full open position Replace the component: A103 Roof Console ⇓ If the liftgate performs the power open function and stops at the garage mode position.
  4. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Roof Console Replacement For control module replacement, programming, and setup refer to: Control Module References