System Overview
System overview
RTI (road traffic information)
The main role of the RTI system (Road and Traffic Information) is to manage the functions for:
- the GPS antenna
- The traffic message channel (TMC) receiver (EU only)
- The FM-MPX receiver (Japan only)
- 5 LCD display screen (only used in systems with a CD changer system)
- 6.5 wide screen LCD display screen (only used in systems with a DVD system)
- Steering wheel buttons
- TV receiver (accessory)
- The remote control (accessory)
- The CD changer (not used for DVD systems)
- DVD player (not use for the CD system).
There are two models of the RTI system, one old and one new version.
The older system has two units, the RTI control unit and the CD changer. In the new system the CD changer has been replaced by a DVD player which is integrated with the RTI control module.
The control module is located in the left section of the cargo compartment.
CDs cannot be played in the RTI system. This is because the system is not compatible with these types of disc.
The RTI system communicates partly with components which are directly connected and partly with other control modules and components via serial communication and Control area network (CAN).
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 a fault.
Diagnostic trouble codes (DTC) are stored in the control module memory. The data can be read off using the diagnostic tool.
A simple way to check that the RTI components are both powered and grounded is to try to insert or remove a CD or DVD. The RTI system is powered and grounded if the disc can be inserted and removed. If this is not functioning, check the power supply and ground for the RTI system.
The RTI system has an internal communication system, Melbus. Communication is between the RTI unit, the TV receiver, the CD changer and the audio module.
Melbus communication consists of three different signals:
- MSCK, clock signal
- MDATA, data signal which transmits information
- MBUSY, indicates whether the data signal is engaged or not.
For information, also see Signal specifications.
Signals
The table below summarizes input and output signals to and from the RTI control module. The signal types are divided into directly connected signals, serial communication and Control area network (CAN) communication. The illustration below displays the same information with the Volvo part numbers.
