GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC C Sierra - 2WD 🢒 DTC 🢒 DTC B3102 Keyless Entry Data Link Circuit Low

Object Number: 367980 Size: MF
Body Control Module Components
Body Control System Schematics
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The body control module (BCM) uses CKT 461 in order to receive the command of the remote control door lock receiver module to LOCK and UNLOCK the doors. When a key fob button is pressed the key fob transmits a radio frequency signal to the remote control door lock receiver module. The signal is decoded and sent to the BCM on CKT 461. The signal then LOCKS or UNLOCKS the doors.

Conditions for Setting the DTC
    • When CKT 461 is shorted to ground.
    • The system voltage must be between 9.0-16.0 volts.
    • The above conditions must be met for 0.5 seconds.

Action Taken When the DTC Sets

The keyless entry (RFA) system will not function properly.

Conditions for Clearing the MIL/DTC
    • The current DTC will clear immediately after the short to ground is corrected.
    • A history DTC will clear after 100 consecutive ignition cycles without a fault present.
    • Use a scan tool in order to clear history and current DTCs.

Diagnostic Aids
    • Always diagnose the first DTC listed on the scan tool.
    • The scan tool must display DTC B3102 as a current code before performing diagnostics.
    • Perform a visual inspection for loose or poor connections at all related components
    • Refer to Intermittents and Poor Connections in Wiring Systems.

Test Description

Step number(s) below refer to the same step number(s) in the Diagnostic Table.

  1. This step determines if the BCM is defective.

    2.

  2. This step determines if the remote control door lock receiver module is defective or if CKT 461 for a short to ground.

Step

Action

Value(s)

Yes

No

1

Was the BCM Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - Body Control System

2
  1. Disconnect the brown BCM (C1) connector.
  2. Remove the comb from the connector.
  3. Backprobe, in order to prevent damage to terminal, with a J 39200 digital multimeter (DMM).
  4. Measure the voltage between CKT 461 (ORN) cavity B4 and ground.

Does the J 39200 DMM display battery voltage?

--

Go to Step 6

Go to Step 3

3
  1. Disconnect the remote control door lock receiver module.
  2. Connect a test lamp to B+ and backprobe in order to prevent damage to the terminal, the brown BCM (C1) connector between CKT 461 (ORN) cavity B4.

Does the test lamp light?

--

Go to Step 4

Go to Step 5

4

Locate and repair the short to ground in CKT 461 (ORN) between the remote control door lock receiver module and the BCM.

Is the repair complete?

--

Go to Step 7

--

5

Replace the remote control door lock receiver module.

Is the repair complete?

--

Go to Step 7

--

6
  1. Replace the BCM. Refer to Body Control Module Replacement .
  2. Program the BCM with the proper calibrations. Refer to Body Control Module (BCM) Programming/RPO Configuration .
  3. Perform the learn procedure

Is the repair complete?

--

System OK

--

7

Clear the DTCs. Refer to Clearing DTCs .

Is the action complete?

--

System OK

--