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Tahoe / Yukon Service Manual

DTC B1AB1

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 Descriptors DTC B1AB1 Rear Window Wiper Motor Circuit/System Description The M45 Rear Wiper Motor communicates with the K9 Body Control Module via LIN and responds to requests to turn the rear wipers on and off, as well as to vary the wiper speed. The M75  Windshield Wiper Motor receives a constant B+ and chassis ground. In operation, the M45 Rear Wiper Motor monitors LIN messages to determine the requested wiper selection is requested. The M45 Rear Wiper Motor includes a DC motor and an internal position switch to indicate the wiper park position. When wiper operation is requested, the DC motor spins. When wiper operation is no longer required, the M45 Rear Wiper Motor will continue spinning until the internal position switch indicates it is in the park position. Conditions for Running the DTC Ignition ON Conditions for Setting the DTC The K9 Body Control Module receives an invalid signal from the M45 Rear Wiper Motor. Conditions for Clearing the DTC The condition responsible for setting the DTC no longer exists. Reference Information Schematic Reference Wiper/Washer Schematics Connector End View Reference Master Electrical Component List Description and Operation Wiper/Washer System Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Control Module References Circuit/System Verification

  1. Ignition ON.
  2. Verify no other DTCs are set. ⇒ If other DTCs are set Refer to Diagnostic Trouble Code (DTC) List - Vehicle ⇓ If no other DTCs are set
  3. Verify DTC B1AB1 is not set current. ⇒ If DTC B1AB1 is set current Replace the M45 Rear Wiper Motor ⇓ If the DTC is not set current
  4. A fault is not currently present and may be an intermittent condition. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Rear Window Wiper Motor Replacement Control Module References