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 Descriptor
DTC B1420: Device VoltageDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+ - Folding Top Control Module | 1 | 1 | -- | -- |
Ignition Voltage | B1420 | B1420 | -- | -- |
5 Bow Lowered Switch Signal | B1420 | 6 | B1291 | -- |
5 Bow Raised Switch Signal | B1420 | 3, 4 | B1291 | -- |
Folding Top Connected Signal | B1420 | 6 | -- | -- |
Folding Top Cover Open Switch Signal | B1420 | 3, 4 | B3666 | -- |
Luggage Barrier Switch Signal 5745 | B1420 | 6 | -- | -- |
Top Closed Switch Signal | B1420 | 3, 4 | B3971 | -- |
Top Open Switch Signal | B1420 | 2, 3, 5, 6 | B3971 | -- |
Ground - Folding Top Control Module | -- | 1 | -- | -- |
1. No communication with the FTC module. 2. Power folding top is inoperative 3. Power folding top does not open or complete the top opening procedure. 4. Power folding top does not close or complete the top closing procedure. 5. Folding top stowage compartment lid release inoperative 6. DIC Warning Message | ||||
Circuit/System Description
The body control module (BCM) applies battery voltage to the accessory voltage circuit when the ignition is in the ON position. The folding top control (FTC) module monitors this circuit at least once every 300 milliseconds to determine if voltage is supplied to the following folding top switches:
| • | Top open switch |
| • | Top closed switch |
| • | Luggage barrier switch |
| • | Folding top cover open switch |
| • | 5 bow raised switch |
| • | 5 bow lowered switch |
| • | Header latched switch |
Conditions for Running the DTC
The FTC module must be powered and can not have B1327 or B1328 set as active DTCs for this DTC to set. The battery voltage is between 9 - 16 volts.
Conditions for Setting the DTC
| • | If the FTC module detects the accessory voltage dropping 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. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Power Folding Top Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Testing
- Ignition OFF, disconnect the X2 harness connector at the FTC module.
- Ignition ON, test for B+ between the ignition circuit terminal D11 and ground.
- If all circuits test normal, replace the FTC module.
| ⇒ | If less than the specified value, test the ignition circuit for a short to ground or an open/high resistance. If all circuits test normal, replace the BCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for FTC module and BCM replacement, setup, and programming
