GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B3602 02: Movable Roof Control Switch short to ground

DTC B3602 5A: Movable Roof Control Switch plausibility failure

Circuit/System Description

S15 and S16 are part of the Folding Top Open/Close switch. The folding top control (FTC) module uses the Folding Top Open/Close switch to determine the appropriate action of the top. S15 is closed and pulls the signal circuit low when holding the Folding Top Open/Close switch in the open position. S16 is closed and pulls the signal circuit low when holding the Folding Top Open/Close switch in the close position.

Conditions for Running the DTC

The FTC module is operational.

Conditions for Setting the DTC

B3602 02

A short to ground is detected on the signal circuit of S15 or S16.

B3602 5A

A short to ground is detected on the signal circuits of S15 and S16.

Action Taken When the DTC Sets

The top is disabled.

Conditions for Clearing the DTC

The fault is no longer present and the top completes one cycle.

Reference Information

Schematic Reference

Folding Top Schematics

Description and Operation

Power Folding Top Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Testing

  1. Disconnect the Folding Top Open/Close Switch.
  2. Use a scan tool to monitor Top Control Switch.
  3. The scan tool should indicate Idle.
  4. If scan tool indicates Opening, test the signal circuit of S15 for a short to ground. If circuit OK, replace FTC Module.
    If scan tool indicates Closing, test the signal circuit of S16 for a short to ground. If circuit OK, replace FTC Module.
  5. If circuits test OK, replace the Folding Top Open/Close Switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Convertible Top Switch Replacement
    •  Folding Top Control Module Replacement