GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The body control module (BCM) controls the rear compartment lid latch. When the BCM receives a release input from the rear compartment lid release switch or the remote control door lock receiver the BCM pulses the rear compartment lid latch and the rear compartment lid opens.

DTC Descriptor

The diagnostic procedure supports the following DTC:

DTC B3247 Short to ground in the rear compartment lid release circuit

Conditions for Running the DTC

The BCM must be commanding the rear compartment lid latch to energize.

Conditions for Setting the DTC

    • The BCM detects a short to ground in the rear compartment lid release output circuit.
    • The condition above must be present for more than 0.15 second.

Action Taken When the DTC Sets

The BCM stores DTC B3247 in memory.

Conditions for Clearing the DTC

    • A short to ground is no longer detected in the rear compartment lid release output circuit.
    • A history DTC B3247 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • A scan tool may be used to clear the DTC.

Diagnostic Aids

    • If the DTC B3247 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 in the rear compartment lid release circuit
       - The rear compartment lid latch is shorted to ground internally.
       - The BCM is shorted to ground internally.

Test Description

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

  1. Listen for the rear compartment lid latch to operate. Repeat the commands as necessary.

  2. This step verifies that the body control module is providing voltage to the rear compartment lid latch.

  3. This step tests for an open in the ground circuit to the rear compartment lid latch.

  4. This step tests if voltage is constantly being applied to the rear compartment lid latch.

Step

Action

Yes

No

Schematic Reference: Body Rear End Schematics

Connector End View Reference: Body Rear End Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the rear compartment lid latch ON and OFF.

Does the rear compartment lid latch turn ON and OFF with each command?

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the rear compartment lid latch.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the control circuit of the rear compartment lid latch and a good ground.
  5. With a scan tool, command the rear compartment lid latch ON and OFF.

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

Go to Step 4

Go to Step 5

4

  1. Connect a test lamp between the control circuit of the rear compartment lid latch and the ground circuit of the rear compartment lid latch.
  2. With a scan tool, command the rear compartment lid latch ON and OFF.

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

Go to Step 8

Go to Step 10

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 rear compartment lid latch 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

7

Test the control circuit of the rear compartment lid latch for a short to voltage. 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 rear compartment lid latch. 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 13

Go to Step 11

9

Inspect for poor connections at the harness connector of the body control module. 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 13

Go to Step 12

10

Repair the ground circuit of the rear compartment lid latch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 13

--

11

Replace the rear compartment lid latch. Refer to Rear Compartment Lid Latch Replacement

Did you complete the replacement?

Go to Step 13

--

12

Important: Perform the set up procedure for the body control module. Refer to Control Module References in Computer/ Integrating Systems.

Replace the body control module (BCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

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