Convertible Top - System Operation and Component Description

convertible top down function requirements have been met (accessory delay relay is active, vehicle speed is less than 5 km/h (3 mph) and the convertible top latch is released) and the convertible top DOWN switch is activated, a ground signal is sent to the Moveable Roof Control Module B (MRCMB). The Moveable Roof Control Module B (MRCMB) sends a convertible top down message over the MS-CAN to the Moveable Roof Control Module A (MRCMA). The Moveable Roof Control Module A (MRCMA) verifies all down function requirements have been met and then sends a window down message over the MS-CAN to the BCMB to lower all 4 windows. The BCMB sends a signal on the global open circuit to the 4 window motors to activate a full down operation of all 4 windows. Once the windows are fully lowered, the full down sensor in each rear quarter window motor sends a signal to the BCMB indicating the windows are in the full DOWN position. The BCMB sends the rear window status message to the Moveable Roof Control Module A (MRCMA) over the MS-CAN. After receiving the rear window status message from the BCMB, the Moveable Roof Control Module A (MRCMA) sends a convertible top down message to the Moveable Roof Control Module B (MRCMB) and the convertible top is lowered.

When the convertible top up function requirements have been met (accessory delay relay is active, vehicle speed is less than 5 km/h (3 mph) and the 2 tonneau covers (if equipped) are not in place) and the convertible top switch UP is activated, a ground signal is sent to the Moveable Roof Control Module A (MRCMA). The Moveable Roof Control Module A (MRCMA) verifies all up function requirements have been met and then sends a window down message over the MS-CAN to the BCMB to lower all 4 windows. The BCMB sends a signal on the global open circuit to the 4 window motors to activate a full down operation of all 4 windows. Once the windows are fully lowered, the full down sensor in each rear quarter window motor sends a signal to the BCMB indicating the windows are in the full DOWN position. The BCMB sends the rear window status message to the Moveable Roof Control Module A (MRCMA) over the MS-CAN. After receiving the rear window status message from the BCMB, the Moveable Roof Control Module A (MRCMA) sends a convertible top up message to the Moveable Roof Control Module B (MRCMB) and the convertible top is raised.

If the convertible top cannot be raised or lowered, the Moveable Roof Control Module A (MRCMA), Moveable Roof Control Module B (MRCMB) or BCMB sets a DTC. There are no warning indicators associated with the convertible top system, but messages may be displayed in the message center.

Convertible Top Drop Window Function

When the convertible top switch is operated (to raise or lower the convertible top), the BCMB sends a signal on the global open circuit to the 4 window motors to activate a full down operation of all 4 windows. When the rear quarter windows reach the full DOWN position, the full down sensor in each rear quarter window motor sends a signal to the BCMB indicating the windows are in the full DOWN position. If the BCMB does not see the full down signal from both rear quarter window motors, the convertible top does not operate. The BCMB also disables the rear quarter window control switch from operating the rear quarter windows when the convertible top is not in the full UP or full DOWN position by sending a message (pulses) on the global open circuit (the front door window motors ignore this message). This function prevents an accidental opening of the convertible top with the windows in the UP position causing contact between the windows and convertible top which may result in damage to the convertible top or windows. For additional information on window operation, Refer to: Glass, Frames and Mechanisms - System Operation and Component Description (501-11 Glass, Frames and Mechanisms, Description and Operation).

Moveable Roof Control Module A (MRCMA) Message Center Messages

The Moveable Roof Control Module A (MRCMA) continually monitors the convertible top system operation and status using Hall-effect switches. The convertible top latch contains a magnet which activates a Hall-effect switch. The Hall-effect switch is hard-wired to the Moveable Roof Control Module A (MRCMA) so the module knows the roof is secured. The optional tonneau covers also each contain a magnet which activates a Hall-effect switch. One Hall-effect switch is hard-wired to the Moveable Roof Control Module A (MRCMA) and the other is hard-wired to the Moveable Roof Control Module B (MRCMB). When one or both tonneau covers are installed, the magnet actives the Hall-effect switch and prevents the convertible top from being raised. The Moveable Roof Control Module A (MRCMA) receives vehicle speed from the PCM over the HS-CAN1. If the vehicle speed exceeds 5 km/h (3 mph), the Hall-effect switches indicates one or more of the tonneau covers are installed or the convertible top latch is not fully engaged the Moveable Roof Control Module A (MRCMA) sends a message to the IPC over the MS-CAN.

When the IPC receives a convertible top status message from the Moveable Roof Control Module A (MRCMA), one or more of the following messages is displayed in the message center:

TOP DISABLED — REMOVE COVERS – Displays when the vehicle occupants attempt to raise the convertible top with the optional tonneau covers installed. TOP DISABLED — REDUCE SPEED – Displays when the vehicle occupants attempt to lower or raise the convertible top and vehicle speed is greater than 5 km/h (3 mph).