GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The roof door module (RDM) monitors the folding top stowage compartment lid latch switch signal circuits at least once every 200 milliseconds. The retractable roof stowage compartment left and right lid latch switches are wired in series. The folding top stowage compartment lid latch switches are limit switches. When the stowage compartment lid is latched, the limit switches are active. When the limit switches are active, the RDM detects a switched ground signal.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1323 Tonneau Down and Latched (single or left) Sensor Circuit

Conditions for Running the DTC

    • The battery voltage is between 9-16 volts.
    • Ignition is in the Accessory or Run position or retained accessory power (RAP) is active.
    • A request for folding top operation has been received by the RDM, and the RDM attempts to operate the folding top.

Conditions for Setting the DTC

    • If the RDM detects the folding top stowage compartment lid in the latched position and the folding top stowage compartment lid extend cylinder is fully extended.
    • The RDM has performed a folding top stowage compartment lid down command for approximately 30 seconds and the RDM does not detect the folding top stowage compartment lid latched signal.
    • An open or high resistance exists in the folding top stowage compartment lid latch switch signal circuit or ground circuit.
    • An open, high resistance, or short to ground in the folding top valve 3 battery positive supply voltage circuit and folding top valve 3 control circuit.
    • A short to ground in the IGN 0 supply voltage circuit to any valve, relay or motor on that circuit.
    • An internally shorted to ground valve or pump motor relay on the IGN 0 supply voltage circuit.

Action Taken When the DTC Sets

    • Stores a current and history DTC B1323 in the RDM.
    • Folding top operation is suspended.
    • Message displayed on the Driver Information Display--ROOF CYCLE TIMEOUT.

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 source of an intermittent fault. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Step

Action

Yes

No

Schematic Reference: Folding Top Schematics

Connector End View Reference: Power Roof Systems 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, observe the Tonneau Safety Switch parameter in the data list for the roof door module (RDM).

The Tonneau Safety Switch with the folding top stowage compartment lid open will display Unlatched and will display Latched with the folding top stowage compartment lid closed.

Does the scan tool display the appropriate state?

Go to Step 3

Go to Step 4

3

  1. Attempt to activate the retractable roof. If the roof will not activate, manually retract the roof. Refer to Folding Top Manual Operation .
  2. With the scan tool, observe the Tonneau Safety Switch parameter.

Does the Tonneau Safety Switch parameter change state?

Go to Step 7

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the left folding top stowage compartment lid latch switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the Tonneau Safety Switch parameter.

Does the scan tool display Unlatched?

Go to Step 5

Go to Step 8

5

  1. Connect a 3-amp fused jumper connected to a good ground to the retractable roof stowage compartment lid latch switch signal circuit harness connector terminal.
  2. Observe the Tonneau Safety Switch parameter in the scan tool.

Does the scan tool display Latched?

Go to Step 7

Go to Step 6

6

Test for an open or high resistance in the folding top stowage compartment lid latch switch signal circuit . 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 for one of the following conditions. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

    • An open or high resistance in the folding top stowage compartment lid latch switch signal circuit between both switches
    • An open or high resistance in the folding top stowage compartment lid latch switch ground circuit
    • An open, high resistance, or short to ground in the folding top valve 3 control circuit
    • An open or high resistance in the folding top valve 3 supply voltage circuit
    • An open or high resistance in either pump relay control circuit
    • A short to ground in the IGN 0 supply voltage circuit to any valve or pump motor relay on that circuit
    • An internally shorted to ground valve or pump relay that is supplied voltage by the IGN 0 supply voltage circuit.

Did you find and correct the condition?

Go to Step 13

Go to Step 10

8

Test the folding top stowage compartment lid latch switch signal circuit 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

9

Inspect for poor connections at the harness connector of the RDM. 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

10

Inspect for poor connections at the harness connector of the folding top stowage compartment lid latch switches. 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

11

Important: Always perform the reinitialization of the power windows procedure for the RDM.

  1. Replace the RDM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
  2. Perform the reinitialization of the power windows procedure for the RDM. Refer to Power Window Reinitialization in Doors.

Did you complete the replacement?

Go to Step 13

--

12

Replace the inoperative folding top stowage compartment lid latch switch. Refer to Folding Top Stowage Compartment Lid Latch Replacement .

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.

Does the DTC reset?

Go to Step 2

System OK