PRECAUTION
- INITIALIZATION NOTE: When disconnecting the negative (-) battery cable, initialize the following system after the cable is reconnected. SYSTEM REFERENCE System Name See procedure Power Window Control «INITIALIZATION»(ref-291101-S25902095052008072400000) Sliding Roof System «INITIALIZATION»(ref-291101-S25902095052008072400000)
- EXPRESSIONS OF IGNITION SWITCH The type of ignition switch used on this model differs according to the specifications of the vehicle. The expressions listed in the table below are used in this information. EXPRESSIONS OF IGNITION SWITCH Switch Type Ignition Switch (position) Engine Switch (condition) Expression Ignition Switch off LOCK Off Ignition Switch on (IG) ON On (IG) Ignition Switch on (ACC) ACC On (ACC) Engine Start START Start
Scheme 59
Scheme 60
SYSTEM DIAGRAM
| Item | Details |
|---|---|
| Number of BEAN connected ECUs*1 | 12 |
| Number of CAN connected ECUs*1 | 7 |
| Number of AVC-LAN connected ECUs*1 | 6 |
| Gateway function between BEAN and diagnosis | Gateway ECU |
| Gateway function between BEAN and AVC-LAN | Gateway ECU |
| Gateway function between BEAN and CAN | Gateway ECU |
| ECU in charge of vehicle customization information | Gateway ECU |
| Protocol | CAN, BEAN and AVC-LAN |
| HINT: *1: Optional ECUs are also included. | |
ITEM DETAILS
Scheme 61
Scheme 62
Scheme 63
Scheme 64
Scheme 65
Scheme 66
Scheme 67
- MULTIPLEX COMMUNICATION SYSTEM BASICS The AVALON multiplex communication uses serial communication, which converts multiple pieces of information into serial communication data. As a result, they can be transmitted through a single communication wire. Serial communication data consist of bits and frames. A bit is a basic unit that represents one piece of information. A bit is represented by the binary values "0" or "1". A frame is a body of data that is transmitted as a packet. A frame contains a "header" that indicates the beginning of the data and an "end" message that indicates the end of the data. Based on serial communication, various ECUs are connected on a network to exchange various pieces of information. Such a system is called a multiplex communication system. The CAN uses a multi star style bus connection. The 3 junction connectors are connected by a main bus line. Junction connectors communicate with ECUs using a sub bus line. The BEAN uses ring and bus styles of networks to connect ECUs. This style of connection is called a daisy chain. In a daisy chain, communication can be maintained even if there is an area that has an open circuit. The AVC-LAN uses a star configuration, which is centered on the multi display or audio head unit. Differences between CAN, BEAN and AVC-LAN Protocols, which are rules for establishing data communication, differ between the CAN, BEAN and the AVC-LAN. If ECUs use different types of data such as communication speed, communication wire, and signals, they will be unable to communicate with each other. Therefore, protocols (rules) must be established among them. COMMUNICATION DATA REFERENCE CHART Control Driving Control System Body Electrical Control System Body Electrical Control System Protocol CAN (ISO Standard) BEAN (TOYOTA Original) AVC-LAN (TOYOTA Original) Communication Speed 500 k bps* (Max. 1 M bps) Max. 10 k bps* Max. 17. 8 k bps* Communication Wire Twisted-pair Wire AV Single Wire Twisted-pair Wire Drive Type Differential Voltage Drive Single Wire Voltage Drive Differential Voltage Drive Data Length 1 to 8 Byte (Variable) 1 to 11 Byte (Variable) 0 to 32 Byte (Variable) HINT: *: The abbreviation "bps" stands for "bits per second" (the number of bits that can be transmitted per second). A single, Automobile Vinyl (AV) wire is used for BEAN communication. A twisted-pair wire is used for CAN and AVC-LAN communication. COMMUNICATION WIRE AND OUTLINE REFERENCE Communication Wire Outline AV Single Wire Lightweight single communication wire that consists of single core line surrounded by insulation. Voltage is applied to this line in order to drive communication. This system is called a "Single Wire Voltage Drive". Twisted-pair Wire for AVC-LAN Twisted-pair Wire for CAN Pair of lines Twisted together and covered with insulation. Communication Is driven by applying positive (+) and negative (-) voltage to the 2 lines in order to send a single signal. This system, which is called "Differential Voltage Drive", can reduce noise.
- NETWORK GATEWAY ECU The network gateway ECU of the AVALON has the following functions: FUNCTION OUTLINE Function Outline Gateway Data for respective protocols (CAN, BEAN and AVC-LAN) are arranged differently. Therefore, it is not possible to exchange data between different protocols. For this reason, data arrangement must be converted before transferring data to a communication bus (CAN, BEAN and AVC-LAN). This conversion is called a gateway function. It is preformed by a gateway ECU. Diagnosis (only for BEAN) By connecting an Techstream to DLC3 and operating the tester, technicians can access ECUs via the gateway ECU and BEAN communication bus. In this manner, DTCs for BEAN can be output, DATA LIST (for checking ECU data) can be displayed, and ACTIVE TEST (to actuate desired actuator) can be performed. Customize (only for BEAN) Customized body electronics system enables control function settings of ECUs to be changed through use of an Techstream. However, this system can change settings only of ECUs that belong to the bus in which communication is centered on gateway ECU.