GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2002 🢒 Regal 🢒 DTC 🢒 DTC B2552

Circuit Description

The Body Control Module (BCM) controls the backup lamp relay. The BCM grounds the backup lamp relay control circuit energizing the backup lamp relay.

Conditions for Running the DTC

Any of the following conditions may be present.

    • The transaxle is not in the reverse position.
    • The emergency vehicle interior lamp switch is enabled.
    • The ignition switch is in the off position.

Conditions for Setting the DTC
    • The fault code will set when the backup lamp relay control circuit is inactive and a short to ground or open is present.
    • The condition above must be present for more than 0.3 seconds.

Action Taken When the DTC Sets

The BCM stores DTC  B2552 in memory.

Conditions for Clearing the DTC
    • A current DTC B2552 will clear if the BCM no longer detects a short to ground or open in the backup lamp relay control circuit.
    • A history DTC B2552 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • The BCM receives a clear code command from the scan tool.

Diagnostic Aids
    • If the DTC B2552 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • The following conditions may cause an intermittent malfunction to occur:
       - An intermittent short to ground or open in the backup lamp control circuit.
       - The backup lamp relay coil is intermittently shorted to ground or open.
       - The BCM is intermittently shorted to ground or open.

Test Description

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

  1. Listen for an audible click when the backup lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.

    2.

  2. Tests for voltage at the coil side of the backup lamp relay. The R/CMPT fuse supplies power to the coil side and the switched side of the backup lamp relay.

    3.

  3. Verifies that the BCM is providing ground to the backup lamp relay.

    4.

  4. Tests if ground is constantly being applied to the backup lamp relay.

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the backup lamp relay ON and OFF.

Does the backup lamp relay display Active and Inactive with each command?

Go to Diagnostic Aids

Go to Step 3

3

Check the R/CMPT REL fuse for an open.

Is the R/CMPT REL fuse open?

Go to Step 12

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the backup lamp relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Using a test lamp connected to ground, probe the coil side supply circuit of the backup lamp relay.

Does the test lamp illuminate?

Go to Step 5

Go to Step 11

5

  1. Connect a test lamp between the control circuit of the backup lamp relay and the coil side supply circuit of the backup lamp relay.
  2. With a scan tool, command the backup lamp relay ON and OFF .

Does the test lamp turn on and off with each command?

Go to Step 9

Go to Step 6

6

Does the test lamp remain illuminated with each command?

Go to Step 8

Go to Step 7

7

Test the control circuit of the backup lamp relay for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 10

8

Test the control circuit of the backup lamp relay for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 10

9

Inspect for poor connections at the backup lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 13

10

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 15

Go to Step 14

11

Repair the open or high resistance in the coil side supply circuit of the backup lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 15

--

12

Repair the short to ground in one of the following circuits:

    • The coil side supply circuit of the backup lamp relay
    • The switch side supply circuit of the backup lamp relay
    • The backup lamps supply voltage circuit

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 15

--

13

Replace the backup lamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 15

--

14

Important: Perform the setup procedure for the Body Control Module (BCM). Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 15

--

15
  1. Use the scan tool in order to clear the DTCs .
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK