• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
B+ - Folding Top Control Module | 1 | 1 | -- | -- |
B+ - Folding Top Cover Pull Down Actuator | 3, 4, 5 | 3, 4, 5 | -- | -- |
B+ - Tonneau Release Relay | 2, 3, 5 | 2, 3, 5 | -- | -- |
Ignition Voltage - Top Open Switch | B1420 | 2, 3, 5, 6 | -- | -- |
Folding Top Cover Pull Down Ajar Signal | 2, 3, 5 | 3, 4 | -- | -- |
Top Open Switch Signal | B1420 | 2, 3, 5, 6 | B3971 | -- |
Folding Top Cover Ajar Signal | 5, 6 | B3666 | -- | -- |
Folding Top Cover Latch Actuator Control | 2, 5 | 2, 3, 5 | 5, 6 | -- |
Folding Top Cover Pull Down Actuator Control | 5 | 3, 4, 5 | -- | -- |
Ground - Folding Top Cover Latch Actuator | -- | 2, 3, 5 | -- | -- |
Ground - Folding Top Cover Pull Down Actuator | -- | 3, 4, 5 | -- | -- |
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 |
The power folding top system includes a folding top cover that is powered open and close by a hydraulic system that is controlled by the FTC module. A power unlatch motor is used to unlatch the folding top cover before the folding top control (FTC) module powers the top cover open. The folding top cover unlatching is requested by the FTC module via class 2 message, but is executed by the body control module (BCM). When requested, the BCM applies battery voltage through the folding top cover release relay control circuit to the tonneau release relay. The relay is energized and battery voltage is applied through the folding top cover release control circuit to the latch actuator. The actuator is energized and the latch releases the folding top cover.
The purpose of the folding top cover pull down actuator is to compress the folding top when its in the down position while the cover is being closed.
Battery positive voltage is supplied at all times to the folding top cover pull down actuator from the TONNEAU RELEASE Fuse located in the BCM fuse block. The pull down actuator is also provided with a control circuit, an ajar status circuit, and a ground circuit.
After the folding top cover latch actuator releases the cover, an internal switch in the actuator opens the control circuit to the pull down actuator commanding it to raise the striker. The pull down actuator will turn itself off once the striker is fully extended. Then with the striker in the extended position, the folding top cover pull down ajar signal circuit is pulled low signaling the BCM the ajar status of the pull down actuator. After the folding top is in the desired position, and the folding top cover is closed and latched, the internal switch in the latch actuator closes pulling the control circuit of the pull down actuator to ground, commanding it to retract the striker. The pull down actuator then reverses polarity of its motor to retract the striker in order to finish closing the cover.
• | When using the scan tool, the folding top cover is referenced as the tonneau. |
• | Whenever the open/close control switch is released or the top becomes inoperative in a suspended state, pressure will be maintained in the hydraulic system to avoid drifting and damage of components. After 4 minutes, the FTC module will gradually release the hydraulic pressure allowing the top to gradually settle to a resting position. |
• | If a repair is made to a signal circuit for a short to ground, test the component of that circuit for proper operation. |
• | Removing the tonneau release relay will set a DTC and stop power folding top operation. Once the relay is replaced, the ignition must be cycled OFF then Run ACCY in order to continue operation. |
Power Folding Top Description and Operation
Control Module References for scan tool information
Important: This diagnostic test is to be used only in conjunction with other diagnostic procedures in this section. Using this diagnostic table without being directed to its use, may result in the misdiagnoses of the power folding top system. Refer to Power Folding Top Inoperative.
⇒ | If the pull down actuator continuously moves up and down, refer to the Folding Top Cover Pull Down Ajar Test. |
⇒ | If not the specified value, refer to the Top Open Switch Test. |
⇒ | If not the specified value, refer to the Folding Top Cover Latch Ajar Test. |
⇒ | If the cover did not unlatch, refer to the Folding Top Cover Latch Actuator and Relay Test. |
⇒ | If the pull down actuator did not extend to the raised position, refer to the Folding Top Cover Pull Down Actuator Test. |
⇒ | If the cover did not latch, refer to the Folding Top Cover Pull Down Actuator Test. |
⇒ | If the pull down actuator did not retract, refer to the Folding Top Cover Pull Down Actuator Test. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp illuminates, test the control circuit for a short to ground. |
⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance.. |
⇒ | If not the specified value, test the signal circuit terminal A for a short to voltage. If the circuit tests normal, replace the FTC module. |
⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the FTC module. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the control circuit terminal 87 for a short to ground. If the circuit tests normal, test or replace the folding top cover latch actuator. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the folding top cover latch actuator does not activate, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the folding top cover latch actuator. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test or replace the folding top cover pull down actuator. |
⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the pull down actuator does not extend and retract, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the folding top cover pull down actuator. |
⇒ | If not the specified value, replace the top open switch. |
⇒ | If not the specified value, replace the top open switch. |
⇒ | If the resistance is not within the specified range, replace the relay. |
• | 30 and 85 |
• | 30 and 86 |
• | 30 and 87 |
⇒ | If not the specified value, replace the relay. |
⇒ | If greater than the specified range, replace the relay. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for FTC module and BCM replacement, setup, and programming |