Diagnostic Aids

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

If the DTC B2533 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
An intermittent short to voltage in the following locations may cause an intermittent malfunction to occur:
- The control circuit of the fog lamps relay
- The fog lamps relay
- The body control module (BCM)

DTC B2533

Step	Action	Yes	No
Schematic Reference: Fog Lights Schematics Connector End View Reference: Master Electrical Component List
1	Did you perform the Diagnostic System Check?	Go to Step 2	Go to Diagnostic System Check - Lighting Systems
2	Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the fog lamps relay ON and OFF. Does the fog lamps relay turn ON and OFF with each command?	Go to Diagnostic Aids	Go to Step 3
3	Turn OFF the ignition. Disconnect the fog lamps relay. Turn ON the ignition, with the engine OFF. Connect a test lamp between the battery voltage circuit of the fog lamps relay coil and ground. Refer to Circuit Testing in Wiring Systems. Does the test lamp illuminate?	Go to Step 4	Go to Step 7
4	Connect a test lamp between the control circuit of the fog lamps relay and the battery voltage circuit of the fog lamps relay coil. Refer to Circuit Testing in Wiring Systems. With a scan tool, command the fog lamps relay ON and OFF. Does the test lamp turn ON and OFF with each command?	Go to Step 8	Go to Step 5
5	Test the control circuit of the fog lamps relay for a short to battery positive voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?	Go to Step 10	Go to Step 6
6	Inspect for a poor connection at the harness connector of the body control module (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 10	Go to Step 9
7	Replace the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you complete the repair?	Go to Step 10	-
8	Replace the fog lamps relay. Refer to Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center) in Wiring Systems. Did you complete the replacement?	Go to Step 10	-
9	IMPORTANT: Perform the set up procedure for the body control module (BCM). Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control Systems. Replace the BCM. Refer to Body Control Module Replacement in Body Control System.Did you complete the replacement?	Go to Step 10	-
10	Use the scan tool in order to clear the DTCs. 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