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Home >> Cadillac >> 2021 >> XT5 Sport >> Repair and Diagnosis >> External Pages >> Different car >> Section 734 (Keyless Entry System And Remote Functions) >> Diagnostic Information and Procedures >> No Remote Detected >> Circuit/System Description
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Circuit/System Description

WARNING: This page is about a different car, the 2023 GMC Sierra 3500 HD and 2023 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

For an overview of the component/system, refer to: Keyless Entry System Description and Operation 

Circuit Description
B+ Supplied by a control module.
Serial Data Digitally encoded information for communication between devices.
Low Reference circuit Grounded through the control module.
Component Description
K9 Body Control Module Depending on the version, the control module can support different functions:
  • Immobilizer Function
  • Central Door Locking
  • Power Mode Control
  • Ignition Key/Shifter Interlock

The control module also reads various switches and sensors and makes their values available via serial data.
K84 Keyless Entry Control Module The keyless entry control module communicates via serial data with the body control module and the auxiliary body control module.