GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The folding top control (FTC) module checks the rear compartment lid (decklid) open switch signal circuit of the rear compartment lid (decklid) open switch, at least once every 300 milliseconds. The FTC module compares the deck lid open signal circuit against the decklid ajar switch, that is sent by class 2 message. As the folding top is starting to operate, the decklid will be released, a class 2 message is sent indicating the decklid ajar switch is ajar. The FTC module will continue to raise the decklid upward until it is fully extended, closing the decklid open switch. The accessory voltage supplied to the decklid open switch will then be applied through the decklid signal circuit to the FTC module. Once this signal is received, the FTC module can continue to cycle the folding top operation.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3669 Deck Lid Position Sensor Circuit

Conditions for Running the DTC

The battery voltage is between 9-16 volts.

Conditions for Setting the DTC

The FTC module monitors the decklid open switch signal switch and the class 2 message of the decklid ajar switch. A DTC is set if both are active.

Action Taken When the DTC Sets

    • Stores a current and history DTC B3669 in the FTC module.
    • The folding top operation is suspended.

Conditions for Clearing the DTC

    • This DTC will clear on the current status after the condition for setting the fault is corrected.
    • A history DTC will clear after 50 consecutive ignition cycles without a fault present.
    • History and current DTC can be cleared using the scan tool.

Diagnostic Aids

If the DTC does not reset after the code is cleared, then the switch may be the intermittent fault. Refer to Testing for Intermittent Conditions and Poor Connections.

Step

Action

Yes

No

Schematic Reference: Folding Top Schematics

Connector End View Reference: Power and Grounding Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Position the decklid in a position other than the fully extended, upward position, to allow access to the decklid open switch.
  4. With a scan tool, observe the Decklid Extended parameter in the Inputs data list for the folding top control (FTC) module.

Does the scan tool display Inactive?

Go to Step 3

Go to Step 4

3

  1. Turn OFF the ignition.
  2. Disconnect the harness connector of the decklid open switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Decklid Extended parameter.

Does the scan tool display Inactive?

Go to Step 6

Go to Step 4

4

Test the signal circuit of the decklid open switch for a short to voltage. Refer to Circuit Testing and to Wiring Repairs.

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Inspect for poor connections at the harness connector of the folding top control module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the decklid open switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

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

Did you complete the replacement?

Go to Step 9

--

8

  1. Replace the decklid open switch. Refer to Rear Compartment Lid Position Switch Replacement .
  2. Perform the setup procedure for the folding top control module. Refer to Power Folding Top Learn .

Did you complete the replacement?

Go to Step 9

--

9

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK