System Overview

System overview

Control module




The Convertible Roof Module (CRM) controls the operation of the Power Retractable Hardtop. The control module manages signals for controlling the hydraulic pump and from the sensors around the roof as well as the functions that can be controlled via the switches.
The control module is connected to CAN LS (Low speed, 125 kbit/s).

The Convertible Roof Module (CRM) is responsible for:
- Monitoring the sensors to be able to check operation of the roof and the load assistance functionality.
- Activating the opening/closing sequence for the roof and load assistance by checking the electric and hydraulic systems.
- Communication with other control modules via the CAN network to control windows via the door control modules, to prevent friction and other problems between the roof sections and windows during the time the roof is operated. The Convertible Roof Module (CRM) is also responsible for deactivating the automatic climate position via the Climate control module (CCM) when the roof is open and to automatically adjust the sound settings in the Infotainment control module (ICM).
- To check the warning conditions, for example, too high a speed, internal faults etc. and to warn the driver through the Driver information module (DIM)
- Locking/unlocking the lockable compartments and the ski hatch lock.
The control module is located in the cargo compartment on the right-hand side behind the panel.
The Convertible Roof Module (CRM) communicates with directly connected components and with other control modules via CAN communication.
The control module checks activations and input and output signals using an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if the control module detects an error. In certain cases the control module replaces the faulty signal with a substitute value.
Diagnostic trouble codes (DTCs) can be stored when the key is in position 0, 1, 2 or 3.
Any diagnostic trouble codes are stored in the control module memory. The information can be read out via the data link connector in the vehicle.
A simple way to ensure that the Convertible Roof Module (CRM) is powered and grounded is to activate one of its functions, for example, operate the roof using its switch.
This document only deals with the control module and its corresponding components. For information about the mechanical parts in the roof system, see Design and Function, Power Retractable Hardtop.

Signals
The table below covers input and output signals to and from the Convertible Roof Module (CRM). The signal type is split into directly connected signals and CAN communication. The illustration below provides the same information with Volvo's component designations.