GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Impala 🢒 Body and Accessories 🢒 Lighting Systems 🢒 DTC B2532 Front Fog Lamps Control Circuit Low

Circuit Description

The Body Control Module (BCM) controls the fog lamp relay. The BCM gets an input from the fog lamp switch input circuit and then energizes the fog lamp relay by grounding the fog lamp relay coil control circuit. The BCM grounds the fog lamp relay coil control circuit if the following conditions exist:

    • The ignition switch must be in the RUN position.
    • The headlamp switch must be in the PARK or HEAD position.
    • The headlamp dimmer switch must be in the LOW position.

Conditions for Running the DTC

The BCM must not be commanding the fog lamp relay to energize.

Conditions for Setting the DTC
    • The BCM detects a short to ground or open in the fog lamp relay coil control circuit when the BCM is not trying to energize the fog lamp relay.
    • The condition above must be present for more than 0.3 seconds.

Action Taken When the DTC Sets
    • The BCM stores DTC B2532 in memory.
    • The SERVICE VEHICLE SOON telltale illuminates.

Conditions for Clearing the DTC
    • A current DTC B2532 will clear if the BCM no longer detects a short to ground or open in the fog lamp relay coil control circuit.
    • A history DTC B2532 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

Diagnostic Aids
    • If the DTC B2532 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 ground or open in fog lamp relay coil control circuit
       - The fog lamp relay coil is intermittently shorted to ground or open internally
       - The BCM is intermittently shorted to ground or open internally

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Listen for an audible click when the fog 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 fog lamp relay. The FOG RLY fuse supplies power to the coil side of the fog lamp relay.

    3.

  3. Verifies that the Body Control Module is providing ground to the fog lamp relay.

    4.

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

Step

Action

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

Go to Step 2

Go toA Diagnostic System Check - Lighting Systems in Lighting Systems.

2

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

Does the fog lamp relay turn ON and OFF with each command?

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the fog lamp relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the coil side feed circuit of the fog lamp relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 10

4

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

Does the test lamp turn ON and OFF with each command?

Go to Step 8

Go to Step 5

5

Does the test lamp remain illuminated with each command?

Go to Step 7

Go to Step 6

6

Test the control circuit of the fog lamp relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

7

Test the control circuit of the fog 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 13

Go to Step 9

8

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

Did you find and correct the condition?

Go to Step 13

Go to Step 11

9

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

Did you find and correct the condition?

Go to Step 13

Go to Step 12

10

Repair the coil side feed circuit of the fog lamp relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 13

--

11

Replace the fog lamp relay.

Did you complete the replacement?

Go to Step 13

--

12

Important: Perform the set up procedure for the Body Control Module .

Replace the Body Control Module. Refer to Body Control Module Replacement in Body Control Systems.

Did you complete the replacement?

Go to Step 13

--

13
  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