Diagnostic Functions

For diagnostics the Rear seat entertainment module (RSE)/DVD-player has a basic internal system check and a start-up procedure for the screens.

The control module is not connected to the vehicle's other CAN networks. This means for example that no diagnostic trouble codes (DTCs) can be read from the control module. All fault tracing must therefore be carried out via symptom fault tracing.

The following is information that may facilitate when fault tracing in the system.

When the ignition is switched on the Rear seat entertainment module (RSE) performs a basic internal system check and starts the start-up procedure with the screens.

If the time from when the ignition is switched on until the system is in standby mode (only the illuminated POWER button is lit) is longer than normal, this indicates a communication fault with the screens.

The start-up times, see SYSTEM START-UP PROCEDURE

Causes of a long start-up time can be: 

• No supply voltage and ground to the screen
• Damaged wake-up signal cable.
• Damaged cables for the internal CAN network (no communication can take place). In connector D on the Rear seat entertainment module (RSE)/DVD-player the CAN network is strapped for the right-hand screen  . The strap is used to support the future expansion of the system with additional devices. If connector D has been damaged, has become dislodged or for some reason there is no connection between both ends of the strap on the CAN cables, it will not be possible to establish communication.

Switch on the system using the POWER button on the DVD player 

If one of the screens does not start when the system is switched on, when the start-up procedure has elapsed over the normal time (without fault), and only the POWER lamp on the control module/DVD player is lit, this indicates a fault with the actual screen or its cables between the screen and the circuit board.

When communication with the control modules/DVD player in this case is okay, both these screens' circuit boards behind the actual screens are OK.

The functionality of the circuit boards can also be checked by switch on the system and checking whether the IR lamps in the bottom of the screen are slightly illuminated.

The IR-lights are lit for about 2 minutes after the system is switched on or when sound is played from a selected audio source.

Switch on the system using the remote control 

If the system is switched on using the remote control aimed towards the right-hand screen, when the voltage supply and ground to the screen are fully functional but for example there is no CAN-communication with the Rear seat entertainment module (RSE)/DVD-player, the screen will be lit and work in LOCAL mode. It will then be possible to show the menus and to adjust the sound and brightness settings.

This can be misinterpreted as the function is OK. However no picture will be shown on screen if, for example, you play a DVD disc or watch the TV. The system will be switched on and the left-hand screen will start. This is because the cables for the IR signals do not go via the CAN network, but go directly to the DVD player and are interpreted.

If the screen works in LOCAL mode this indicates that the voltage supply and ground to the screen's circuit board are OK.