B3101
DTC B3101
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC B3101 00
- Keyless Entry Data Link Circuit
Diagnostic Fault Information
Circuit/System Description
The body control module (BCM) communicates with the remote control door lock receiver through the keyless entry serial data circuits. When any button on the keyless entry transmitter is pressed, the transmitter sends a signal to the remote control door lock receiver. The remote control door lock receiver sends a function request to the BCM, depending on which button is pressed on the transmitter. The BCM receives the message and performs the appropriate function.
Conditions for Running the DTC
A button is pressed on the keyless entry transmitter.
Conditions for Setting the DTC
No response is received from the remote control door lock receiver after the BCM requests information from or sends configuration commands to the remote control door lock receiver.
Action Taken When the DTC Sets
In the case of power failure, the remote control door lock receiver is disabled for 65 seconds, otherwise no action is taken.
Conditions for Clearing the DTC
* A current DTC will clear when the fault is no longer present.
* A history DTC will clear after 40 consecutive ignition cycles without a fault present.
Reference Information
Schematic Reference
Remote Function Schematics ([1][2]Electrical Diagrams)
Component Connector End Views
Component Connector End Views (Connector End Views By Name)
Description and Operation
Keyless Entry System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the K77 remote control door lock receiver.
2. Ignition OFF, test for less than 30 Ohms between the low reference circuit terminal 1 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K9 BCM.
3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
4. Test for 3-6 V between the serial data circuit terminal 3 and ground.
• If greater than the specified range, test the serial data circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.
• If less than the specified range, test the serial data circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 BCM.
5. Ignition OFF, disconnect the X1 and X2 harness connectors at the K9 BCM.
6. Ignition ON, test for less than 1 V between the K9 BCM serial data circuit terminal 27 X2 and ground.
• If greater than the specified range, test the serial data circuit for a short to voltage.
7. Ignition OFF, test for infinite resistance between the K9 BCM serial data circuit terminal 27 X2 and ground.
• If not the specified value, test the serial data circuit for a short to ground.
8. Test for less than 2 Ohms between the K9 BCM serial data circuit terminal 27 X2 and the K77 remote control door lock receiver serial data circuit terminal 2.
• If greater than the specified range, test the serial data circuit for an open/high resistance.
9. If all circuits test normal, replace the K77 remote control door lock receiver. Verify DTC B3101 is not set.
• If the DTC is set, replace the K9 BCM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for BCM or remote control door lock receiver replacement, programming and setup