GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2006 🢒 Rendezvous - AWD 🢒 DTC 🢒 DTC B2553

Circuit Description

The body control module (BCM) controls the backup lamp relay. The BCM grounds the backup lamps relay control circuit energizing the backup lamp relay. The BCM connects directly to the center console fuse block with no external wiring between them.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B2553 Backup Lamps Control Circuit High

Conditions for Running the DTC
    • The transaxle must be in the REVERSE position.
    • The ignition switch must not be in the OFF position.

Conditions for Setting the DTC
    • The BCM detects a short to voltage in the backup lamp relay control circuit when the BCM tries to energize the backup lamp relay.
    • The condition above must be present for more than 0.3 seconds.

Action Taken When the DTC Sets

The backup lamps will not illuminate.

Conditions for Clearing the DTC
    • A current DTC will clear when the BCM no longer detects a short to battery in the backup lamp relay control circuit.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Current and history DTCs can be cleared when the BCM receives a clear code command from a scan tool.

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

Test Description

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

  1. Verifies that the BCM or backup lamp relay is at fault.

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Important: This DTC may set under normal operating conditions. If the Backup Lamp System operates properly and there is no customer complaint related to the Backup Lamp System, do not continue with this diagnostic procedure.

  1. Block the drive wheels
  2. Press the brake pedal
  3. Place the gear selector in the REVERSE position and back to the PARK position.

Do the backup lamps operate as expected?

Go to Diagnostic Aids

Go to Step 3

3

  1. Disconnect the backup lamp relay.
  2. Using a scan tool, clear the DTC.
  3. With the brake pedal pressed, place the gear selector in the REVERSE and back to the PARK positions.
  4. Using a scan tool, test for DTCs.

Does DTC B2553 reset?

Go to Step 4

Go to Step 5

4

Inspect for poor connections at the harness connector of the backup lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 8

Go to Step 6

5

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 8

Go to Step 7

6

Replace the backup lamp relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 8

--

7

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 8

--

8
  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