GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Regal 🢒 Body and Accessories 🢒 Body Control System 🢒 DTC B3103 RFA Link Circuit Shorted to B+

Object Number: 385169 Size: SF

Circuit Description

The keyless entry system allows the driver to do the following functions from outside the vehicle by using a hand held radio transmitter:

    • Unlock the door locks. The courtesy lights activate automatically when using this function.
    • Lock the door locks.
    • Release the rear compartment lid.
    • Remote alarm.

The transmitter operates in the UHF band. The transmitter sends digitally coded signals to the Remote Control Door Lock Receiver (RCDLR) when pressing any of the transmitter buttons.

The RCDLR detects and decodes transmitter signals. For locking, unlocking, and remote alarm commands, the RCDLR sends command messages to the Body Control Module (BCM) to operate the door locks actuators, courtesy lights, and remote alarm.

Conditions for Setting the DTC

The BCM detects a short to B+ in circuit 377 while attempting to enable the transmitter programming/diagnostic mode.

Action Taken When the DTC Sets
    • The BCM stores DTC B3103 in memory.
    • The RCDLR does not enter transmitter programming/diagnostic mode.

Conditions for Clearing the DTC
    • Current DTC B3103 clears automatically upon entering the transmitter programming/diagnostic mode.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the fault is no longer present.
    • Using a scan tool.

Diagnostic Aids
    • The following conditions may cause an intermittent malfunction to occur:
      • An intermittent short to B+ in circuit 377.
      • An intermittent short to B+ in the BCM.
      • The RCDLR is shorted to B+ internally.
    • The BCM checks for DTC B3103 only when attempting to enable transmitter programming/diagnostic mode. Refer to Transmitter Programming in Keyless Entry for more information on how to enter this mode.
    • The problem may be intermittent. Try performing the tests shown while moving wiring and connectors. This can often cause the malfunction to reappear.
    • DTC P1626 will set in the Powertrain Control Module (PCM) when the ignition switch is on with the Body Control Module (BCM) disconnected. When BCM diagnostics and repairs are completed, refer to Engine Controls for additional information on PCM related DTCs.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step checks for communication between the BCM and the RCDLR when using the keyless entry transmitter.

    2.

  2. This step checks for communication between the BCM and the RCDLR when entering the transmitter programming/diagnostic mode.

    3.

  3. This step checks for a short to B+ in circuit 377.

    4.

  4. This step checks for a faulty RCDLR.

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. Remove key from the ignition switch.
  2. While observing the door locks, press lock using the keyless entry transmitter.
  3. While observing the door locks, press unlock using the keyless entry transmitter.

Did the door locks lock and unlock by using the keyless entry transmitter?

--

Go to Step 3

Go to Step 4

3

  1. Turn the ignition switch to the ON position.
  2. Clear BCM DTCs. Refer to Clearing DTCs for more information.
  3. Attempt to enable the transmitter programming/diagnostic mode. Refer to Transmitter Programming in Keyless Entry for service procedure.
  4. Check for BCM DTCs. Refer to Diagnostic Trouble Code (DTC) Displaying for more information.

Does DTC B3103 reset as a current or history DTC?

--

Go to Step 6

Go to Step 9

4

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the BCM connector C1.
  3. Disconnect the RCDLR.
  4. Using a DMM, measure the voltage between the BCM harness connector C1 terminal C15 and ground.

Is the voltage measured within the specified range?

Less than 2 V

Go to Step 5

Go to Step 7

5

  1. Turn the ignition switch to the OFF position
  2. Reconnect the BCM.
  3. Turn the ignition switch to the ON position.
  4. Use the Device Control function on a Tech 2 scan tool, activate the RFA link output.
  5. Using a DMM, measure the voltage by backprobing between the BCM harness connector C1 terminal C15 and ground.

Is the voltage measured within the specified range when the RFA link was active?

Less than 2 V

Go to Step 6

Go to Step 8

6
  1. Replace the BCM. Refer to Body Control Module Replacement for more information.
  2. After replacing the BCM, perform the Setup New BCM procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration for more information.

Is the repair complete?

--

Go to Step 10

--

7

Repair short to B+ in circuit 377.

Is the repair complete?

--

Go to Step 10

--

8

Replace the RCDLR. Refer to Remote Control Door Lock Receiver Replacement in Keyless Entry for service procedure.

Is the repair complete?

--

Go to Step 10

9

The malfunction is not present at this time. Refer to Diagnostic Aids for additional information regarding this DTC.

Is the repair complete?

--

Go to Step 10

--

10
  1. Turn the ignition switch to the OFF position
  2. Reinstall connectors/components removed.
  3. Turn the ignition switch to the ON position.
  4. Clear BCM DTCs. Refer to Clearing DTCs for more information.
  5. Check for BCM current DTCs. Refer to Diagnostic Trouble Code (DTC) Displaying for more information.

Are there any BCM current DTCs set?

--

Go to Diagnostic System Check - Body Control System

System OK