Folding Top

DTC B1420

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptors
DTC B1420
- Device Voltage

Diagnostic Fault Information









Circuit/System Description

When the ignition is in the ON position, battery voltage from the auxiliary relay is applied through the 15-amp FOLDING TOP/TRUNK LATCH fuse and the control circuit to the folding top control (FTC) module. The FTC module monitors this circuit at least once every 300 milliseconds to determine if voltage is supplied to the following folding top switches:

* Front latched switch
* Front unlatched switch
* Compartment partition switch
* Rear compartment lid open switch or deck lid open switch
* Folding top closed switch
* Rear compartment lid pulldown actuator

Conditions for Running the DTC

The battery voltage is between 9-16 volts.

Conditions for Setting the DTC

* The FTC module detects the control circuit voltage dropped below 3 volts.
* The power mode is either in Accessory, RUN, Rap or Crank.

Action Taken When the DTC Sets

* Stores a current and history DTC B1420 in the FTC module.
* The folding top operation is suspended.
* If the condition occurs during operation of the folding top, once the top control switch is released, the FTC module will send a class 2 message to the driver information center (DIC), displaying TOP NOT SECURE.

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.

Diagnostic Aids

The Rear Compartment Lid is also referenced as the Deck Lid for this vehicle.

Reference Information
Schematic Reference

Folding Top Schematics ([1][2]Convertible Top)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Power Folding Top Description and Operation (Power Folding Top Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for Scan Tool Information

Circuit/System Testing

1. Ignition OFF, disconnect the X2 harness connector at the FTC module.
2. Ignition ON, verify that a test lamp illuminates between the control circuit terminal D11 and ground.

• If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance.

3. If all circuits test normal, replace the FTC module.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

Control Module References (Programming and Relearning) for FTC module replacement, setup, and programming