GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The roof door module (RDM) monitors the folding top valve control output circuits from the RDM at least once every 3 milliseconds. The folding top control valves have ignition 0 voltage supplied. As the folding top control switch is applied to either the open or close position, the RDM will apply the appropriate folding top valve control signals, channeling the specific hydraulic passage/pressure to move the roof system in the correct sequence.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3674 Convertible Top/Moveable Roof Control Valve 1 Circuit

Conditions for Running the DTC

    • The battery voltage is between 9-16 volts.
    • Ignition is in the Run or Accessory position or retained accessory power (RAP) is active.

Conditions for Setting the DTC

    • If the RDM detects a short to power on the folding top control valve control circuit.
    • If the RDM detects an open or short to ground on the folding top control valve control circuit.
    • If the RDM detects an open or high resistance on the folding top control valve supply voltage circuit.

Action Taken When the DTC Sets

    • Stores a current and history DTC B3674 in the RDM.
    • Also stores a current and/or history DTC B3675, B3676, B3677, or B3683 in the RDM in any combination.
    • The roof 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 multiple DTCs are present always diagnose the lowest DTC first.
    • 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 in Wiring Systems.

Step

Action

Yes

No

Schematic Reference: Folding Top Schematics

Connector End View Reference: Power and Grounding Connector End Views in Wiring Systems

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 valves 1 thru 4 ON and OFF.

Does each valve turn ON and OFF with each command?

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the harness connector of the inoperative valve.
  3. Turn ON the ignition, with the engine OFF.
  4. Probe the ignition 0 supply voltage circuit of that valve 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 inoperative valve and the ignition 0 supply voltage circuit of the valve.
  2. With a scan tool, command inoperative valve 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 inoperative valve 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 inoperative valve 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 inoperative valve. 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 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 12

10

Repair the ignition 1 voltage circuit of the inoperative valve. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 13

--

11

Replace the valve. Refer to Folding Top Pump with Motor Replacement .

Did you complete the replacement?

Go to Step 13

--

12

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

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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