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Communication bus systems Communication bus systems Course code: CS03 Student training manual Suzuki Online Training
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Page 1: Communication bus systems - Suzuki Autotraining.suzukiauto.co.za/SASATrainingDocs/CS03...• Communication bus systems practical act ivies CS02 Control Systems I Body Electrical This

Communication bus systems

Communication bus systems Course code: CS03

Student training manual

Suzuki Online Training

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Foreword Networks for data communication, also known as bus systems or protocols, are widely used in today’s motor vehicles. Various components such as sensors, actuators or computers – “nodes” – are connected to each other via a single channel which can consists of one or several wires. A wealth of data is exchanged via this channel. In this training manual, we will study fundamentals of networking systems used in Suzuki vehicles.

Suzuki Technician curriculum This training manual is part of the Non Suzuki Technician to Suzuki Technician curriculum. The curriculum consists of the following modules: 1. GE01 Suzuki Introduction 2. GE02 Electrical / Electronics 3. GE03 Diagnostics 4. EN02 Engine Mechanical part I 5. EN03 Engine Mechanical part II 6. EN04 Engine Mechanical part III 7. EN05 Engine Auxiliary systems 8. DS01 Driveshaft/Axle 9. DS02 Driveshaft/Axle transfer case 10. BR02 Brake control systems 11. Manual transmission / transaxle 12. CS02 Control system / body electrical 13. CS03 Communication / bus systems You are currently studying CS03 Control systems/Body electrical. This module consists of the following courses: • Communication bus systems • Communication bus systems practical act ivies

This document is intended solely for training purposes only. All vehicle repairs and adjustments must be carried out according to the procedures stipulated in current service manuals and technical bulletins.

Smart manuals Some sections of this training manual contain videos with detailed information on the topics you are studying. If you are studying this training manual on a PC, look out for the “green play video” symbol on any photo or picture in this manual, click on the green button to watch a video providing you with detailed information on that topic. Note: Internet connection required.

CS02 Control Systems I Body Electrical 2

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Table of contents Topic Page Bus systems 4 Types of serial communication 4 Classification of bus systems 5 Communication network topology 5 CAN 7 Data transmission 7 Voltage levels 8 CAN message format 8 Controlling bus access 9 Filtering of incoming data messages 10 CAN network hardware 11 Data transmission system 11 Reflection free termination 11 Network nodes 12 Suzuki CAN communication topology 13 LIN 21 Data transmission in the LIN bus 22 LIN protocol 22 Application of LIN bus in Suzuki vehicles 23 UART communication bus 24 Application of UART in Suzuki vehicles 24 Serial Communication 25 Application of serial communication Suzuki vehicles 26

Topic Page Diagnosis 27 DLC 27 Measurement options 27 List of abbreviations 30

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1. Bus systems Communication for each control module and device is established through continuous input/output of ON/OFF digital signals with various data items being managed in parallel. Transmitting/receiving this data is called serial communication interface. The following protocols have been adopted for in-car communication systems on Suzuki vehicles.

1.1 Types of serial communication Types of serial communication interface such as UART, CAN and LIN protocols (communication standards) have been adopted for in-car communication system in Suzuki vehicles. UART UART is a type of "asynchronous receiver/transmitter", a piece of computer hardware that translates data between parallel and serial forms. UART is used for example in the communication from keyless start control module to steering lock unit.

LIN LIN is a single wire communication system used for communication between sensors and actuators in the body electronics area. LIN is used for example in the communication from keyless start control module to each front power window motor and power window master switch, for communication from combination meter to parking sensor system control module, and for communication from HVAC control module to auto A/C panel.

CAN The CAN system is a twisted pair of two communication lines (CAN High and CAN Low) connected between electronic control modules. Data obtained by a specific control module can be shared with other control modules connected to the CAN network. In some Suzuki models for example, the keyless start control module, BCM, ECM, TCM (CVT model), combination meter, P/S control module, HVAC control module, ESP® control module, 4WD control module (4WD model), SDM, steering angle sensor, and rain / light sensor are transmitted/received through CAN.

K-line The K-line bus system consists of a single wire. It is not used for communication between control modules by exclusively for diagnosing an individual control module. In modern vehicles, the K-line bus system is increasingly being replaced by the CAN bus system.

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1.2 Classification of bus systems

1.3 Communication network topology Control modules, some intelligent sensors and actuators are connected to each other using communication networks. Figure 1 shows a typical network topology. The control modules connected to the communication network vary according to vehicle’s equipment level. In most Suzuki vehicles, the network topology consists of mainly the Class C (High Speed CAN) and the Class A (LIN) bus systems. The UART serial communication and K-line can also be found in some models.

Class Transfer rates Applications Representative

A Low data rates, up to 10 kBit/s

Actuator & sensor networking LIN

B Average data rates, up to 125 kBit/s

Complex mechanisms for error handling, control unit networking

Low speed CAN

C High data rates, up to 1 Mbit/s

Real time requirements, control unit networking in the powertrain functions

High speed CAN

C+ Extremely high, up to 10 Mbit/s

Real time requirements, control unit networking in the powertrain functions

FlexRay

D Extremely high, >10 Mbit/s

Control unit networking in the telematics and multimedia functions

MOST

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Communication network topology

Figure 1: Network topology (Suzuki Kizashi A6B424 2WD CVT model)

Junction Connector

Combination meter

Keyless start control

Steering angle sensor SDM Rain/Light

sensor HVAC

BCM

DLC

ABS/ESP Junction Connector

CVT Power Steering ECM

Front Power window motors

Front Power window master switch

A/C control panel

Parking sensor control module

Steering lock

CAN

UART

LIN

Keyless entry receiver

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2. CAN communication CAN communication system is a serial communication system for transmitting a multiple data items (values from sensors, control data and control signals) as ON-OFF digital signals through communication lines. This system uses two lines (CAN High and CAN Low) for the communication circuit so as to maintain high reliability even when used for high-speed serial communication. CAN has the following advantages: a) Less wiring is used for communication between electronic

control modules which results in reduced production costs.

b) Sensor signals can be used by multiple electronic control modules without the need for additional wiring or sensors.

c) Improved reliability and functional reliability due to fewer connectors.

d) Simple connection of system components to a bus.

CAN protocols The CAN bus system has four different protocol formats, each suitable for a specific application. a) Data transmission protocol b) Data request protocol c) Fault message protocol d) Overload message protocol

2.1 CAN overview 2.1.1 Data transmission To communicate, the CAN bus uses two states “dominant” and “recessive”, with which the information bits are transmitted. The dominant state represents “0” and the recessive state represents “1”. Data is transmitted in the CAN bus system using two-wire harness. The first wire is called CAN_H and the other wire is called CAN_L. The two wire system facilitates a symmetrical data transfer in which the bits are transferred via both bus lines using different voltages. This reduces sensitivity to common-node interference, since interference affects both lines and can be filtered out. The wires are twisted together so that any interference affects both CAN_H and CAN_L equally.

1

0

Figure 2: CAN data signal “0” Dominant “1” Recessive

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2.1.2 Voltage levels The CAN High (CAN_H) and CAN Low (CAN_L) use different voltage levels to transfer dominant and recessive states. with 2.5 V as the reference level for both CAN High signal and CAN Low signal. The range of CAN High signal is from 2.5 V to about 3.5 V and that of CAN Low signal is from 2.5 V to about 1.5 V. When both are at 2.5 V, signal is judged as OFF.

When CAN High signal is 3.5 V and CAN Low signal is 1.5 V (that is, when the difference between High voltage and Low voltage is about 2 V), signal is judged as ON. For this reason, the signal waveform between CAN High and CAN Low signals is symmetrical with respect to 2.5 V level. CAN communication fails when the symmetrical signal form collapses.

2.1.3 CAN message format

Message frame

Data frame

Idle 1* 12* 6* 0…….64* 16* 2* 7* 3* Idle 0

1

A B C D E F G H

Figure 4: CAN message format

Figure 3: Data transmission in a CAN line

[A] Start of message [B] Arbitration field [C] Control field [D] Data field [E] CRC field [F] ACK field [G] End of message [H] Inter-message space

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For data transfer on the CAN bus, a message frame is created. The message frame contains the information to be transmitted arranged in a specific sequence. The message transmission sequence is as illustrated in figure 4 and described as follows: A) Start frame The bus state is recessive (1) in the idle state. The start of the frame is represented by a dominant bit and indicates the start of data transmission. B) Arbitration field The arbitration field is made up of 12 bits (11 bit identifier followed by SRR 1 (substitute remote request ) bit). Since only one message can be transmitted using the bus at a time, the arbitration field is used to determine the priority of data to be transmitted. C) Control field The control field contains the code indicating the number of data bytes in the “data field” D) Data field The data field contains the actual message being sent e.g. engine coolant temperature. This message consists of between 0 and 8 Bytes. E) CRC field The CRC (Cyclic Redundancy Check) contains a checksum for detecting possible transmission interference.

F) ACK field The ACK (acknowledgement) field contains the acknowledgement signals with which the receivers indicate the error-free receipt of a message. Only correct receipt is confirmed and this signals to the sender that no malfunction occurred during data transfer. G) End of message The end of message contains 7 recessive bits and marks the end of the data transmission. H) Inter-message space This frame consists of 3 bits is used to separate messages being sent in the bus system.

2.1.4 Controlling bus access If the bus is in the recessive state (unoccupied), messages are available for sending. Each of the control modules connected to the bus can begin sending a message. A message begins with a dominant bit (start of message bit), followed by the identifier. When several control modules begin sending a message simultaneously, the system resolves the conflict by employing arbitration. The message with the highest priority (lowest binary value of the identifier) is allowed first access to the bus. Each station outputs the identifier of its message onto the bus bit by bit, with the most significant bit first.

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Figure 5 shows an example of messages being sent simultaneously from the HVAC, CVT, ABS/ESP control modules. The following start transmitting the following messages at the same time. The HVAC and CVT data messages lose bus access allowing only the data message from the ABS/ESP to use access the bus first. HVAC – Blower fan step signal ABS/ESP – Torque up/down request signal CVT – Fluid temperature signal

2.1.5 Filtering of incoming data messages Each message sent by any of the control modules connected to the CAN bus have a unique marker or identifier. The identifier classifies the content of the message e.g. engine temperature. Each control module is able to broadcast a message to all other stations. These station s read only those messages whose identifiers are stored in their acceptance list. When a control module receives a broadcast message, it whether or not it needs the message or not. If it the control module receives messages that it does not need, it will ignore the message. On the other hand, if a control module receives a message that needs, it will accept the message.

[A] HVAC signal loses the arbitration [B] CVT signal loses the arbitration

1

0

1

0

1

0

HVAC

ABS/ESP

CVT

A B

Figure 5: Bit arbitration CAN_L

CAN_H

Data accept

Reception

Reception

Send message

Provision

Reception

Data Ignored

Data accept

Reception

Reception

Combination Meter ECM BCM TCM

Figure 6: Addressing and message filtering

Engine speed message sent by engine control module to CAN bus network

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2.2 CAN network hardware

2.2.1 Data transmission system Electronic control modules are connected to the CAN network in parallel as shown in figure 6. It is possible to connect at least 30 electronic control modules to the bus without the need for additional measures.

2.2.2 Reflection free termination Reflections of the electrical signals at open ends of lines would interfere with communication. To dampen these reflections, the bus lines are terminated at each end with a resistor of 120Ω (shown in item 1 and 4 of figure 6). Alternately the control terminating resistors can be integrated in the control modules themselves. For example, in the Suzuki Kizashi, the terminating resistor are installed in the ECM and the Combination Meter.

CAN_H

CAN_L

1

2 3

4

Figure 6: Structure of the CAN network

[1] Combination meter [2] ABS control module [3] TCM control module [4] ECM [5] Terminating resistor

5 5

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2.2.3 Network nodes The electronic control modules attached to the CAN system have network nodes. The network nodes have the application software, the CAN transceiver and the CAN controller . The CAN controller generates the bit stream for data communication from the binary data to be transmitted and forwards it to the transceiver on the TxD line. The Transceiver amplifies the signals, generates the voltage level required for differential data transfer and transmits the processed bit stream serially on the CAN bus lines. Incoming messages are processed by the transceiver and sent to the CAN controller on the RxD line. The microcontroller which runs the application program (Engine Control or ABS/ESP control etc.) controls the CAN controller, prepares the data to be sent and evaluates the data received.

Microcontroller

CAN controller

CAN transceiver

CAN RxD CAN TxD

Sensors Actuators

Figure 7: Network nodes

CAN_L

CAN_H

• A data bit can either be ON (1) or OFF (0) • There are 8 bits in 1 byte • 256 different pieces of information can be

transmitted using 8 bits (1 byte) • Data is transmitted serially in the CAN bus system • The CAN, LIN, K-line & UART have been employed in

Suzuki vehicles. • Two terminating resistors are installed in the CAN

bus system. Each resistor has a resistance value of 120Ω.

• The two CAN bus wires are twisted to improve transmission reliability.

• The data message transmitted in the CAN_H wire is symmetrically sent in the CAN_L wire as well.

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2.3 Suzuki CAN communication topology In the following pages, we will look at how the CAN bus system is used in some Suzuki models. What messages are transmitted and received by what control modules in the network. Please refer to the vehicle relevant service manuals for details of models not mentioned in this training manual.

3.1 Suzuki Alto (AMF310) CAN bus system

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3.1.2 Bus systems employed • CAN (Class C (High speed)) 3.1.3 Transmitting and Receiving data table

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Transmitting and Receiving data table (Continued)

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3.2 Suzuki Swift (AZH414) CAN bus system 3.2.1 CAN System diagram

CAN

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3.2.2 Bus systems employed • CAN (Class C (High speed)), UART, LIN.

3.2.3 Transmitting and Receiving data table

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3.3 Suzuki Kizashi (A6B424) CAN bus system 3.3.1 CAN system diagram

[A] CAN communication line [B] 4WD model [C] 2WD model

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3.3.2 Bus systems employed • CAN (Class C (High speed)), LIN, UART 3.3.3 Transmitting and Receiving data table

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• Transmit (T): When 2 controllers start transmitting at the same time, the controller that is transmitting the information with the higher priority obtains the transmission permission and all other controllers enter the receiving mode.

• Receive (R): All data that is transmitted from the controllers is shared on the CAN communication line. The controllers receive only the information that they require from this data, which they can use in their control.

Note: The ECM calculates the vehicle speed based on the wheel speed information that is transmitted from the ABS control module. The ECM then transmits the vehicle speed information to other control modules via the CAN bus.

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3. LIN 3.1 Overview The increasing use of mechatronic systems in the motor vehicle gave rise to the idea of designing a cost-effective bus system as an alternative to the low-speed CAN. The LIN bus is suitable for low data rates of up to 10 kBit/s and is typically limited to a maximum of 16 bus subscribers. These subscribers can be intelligent sensors, actuators or switches with additional hardware for the LIN bus interface. A LIN data bus system is made up of a LIN master and LIN slaves and the data bus wire. Terminating resistors are not used in the LIN data bus system.

3.1.1 LIN communication signal

1

2

3

4

Figure 8: LIN bus with master and slave nodes (Suzuki Kizashi power window system shown)

[1] Keyless start control module [2] Driver side power window motor [3] Passenger side power window motor [4] Power window master switch

LIN bus

Figure 9: LIN signal

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3.1.2 LIN master The LIN master has information on the time sequence of all the data to be transmitted in the LIN bus. The LIN master carries out the following tasks: • The software of the LIN master features a cycle which

determines when and how often what messages are transmitted on the LIN data bus.

• It checks the speed at which data is transmitted in the LIN bus system.

• It performs conversion of the data transmitted. • It performs diagnosis of the LIN slaves

3.1.3 LIN slaves LIN slaves include sensors that evaluate measured values and send information to the LIN master. Transmission takes place in the form of digital signals via the LIN data bus system. It also includes LIN actuators/modules. LIN actuators/modules receive commands from the LIN master. In the LIN bus system shown in figure 8, the power windows are controlled by ECUs build-in the power window motors. Operations of the power window ECU’s are monitored by the keyless start control module.

3.2 Data transmission in the LIN bus The LIN bus system is a single-wire line that is unshielded. The bus may adopt two logical states. • The dominant level corresponds to the electrical voltage of

approximately 0V and represents logical 0 state. • The recessive level corresponds to battery voltage and

represents logical 1 state.

3.2.1 LIN protocol 3.2.2 .1 Frame The information transferred on the LIN bus is embedded in a defined frame. A message initiated by the master always begins with a header. The message field (response) contains different information depending on the type of message.

Figure 10: LIN message

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3.3 Application of LIN bus in Suzuki vehicles 3.3.1 Suzuki Kizashi (A6B424) 3.3.2 Suzuki Swift (AZH412/414)

3.2.2.2 Header The header is composed of the following: • Synchronization break (at least 13 dominant bits) • Synchronization field (consists of bit sequence 01010101).

This bit sequence causes all the connected LIN slaves to synchronize to the internal clock of the LIN master.

• Identifier field (8 bits)

3.2..2.3 Identifier The third byte in the header is used as the identifier 3.2.2.4 Data field The actual data follows the protocol header. The data have length of 1 to 8 data fields. A data field consists of 10 bits. Each data field is composed of a dominant start bit, a data byte (8 bits) and a recessive end bit. The start and end bits serve for post-synchronization and consequently for preventing transmission errors.

Keyless Start control Module

Passenger side power window

motor

Driver side power window

motor

Master window switch (Driver’s

door)

Combination Meter

Parking sensor system control

module

HVAC control module

Auto A/C control panel

HVAC control module

Auto A/C control panel

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4. UART communication bus

4.1 Overview The microcontrollers that are used in control units have a simple interface called UART (Universal Asynchronous Receiver/Transmitter) on the chip, via which they can communicate with other devices. If no data is being exchanged, the bus level is 5V. When the start bit is transmitted (dominant level), the other station connected to the bus (receiver) is notified that a data transfer is starting.

After the start bet has been received, the transmission of an 8 bit (1 byte) data word commences. The receiver that has synchronized itself to the start bit scans the data bus between each data bit and therefore assembles the transferred data byte. The eighth data bit is followed by the parity bit. This bit indicates whether the number of transmitted ones is odd or even. This allows the receiver to perform a simple check of possible errors. The sequence is completed by the stop bit.

4.2 Application of UART in Suzuki vehicles The UART communication bus is employed between the keyless start control module and the steering lock in the vehicles equipped with the keyless start system.

1 2

3 4

Figure 11: UART interface transmission frame

[1] Start bit [2] 8 data bits (1 byte) [3] Parity [4] Stop bit

Keyless Start Control Module Steering Lock

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5. Serial communication

5.1 Overview The data contained in one serial communication is called a frame. 1 frame is made up of multiple bytes. 1 byte is made up of a start bit, a data section and a stop bit. The data section is made up of 8 bits arranged in a series. Each bit is assigned to an information item for communication. By changing the bits that correspond to the information items between HI and LO, multiple information communications can be performed on a single communication line. When there are multiple communication destinations, multiple frames are generated in a single communication cycle. Note that the frame length varies depending on the communication.

Figure 12: Serial communication message frame

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5.2 Application of serial communication The network topology below shows an example of application of serial communication.

Figure 13: Network topology (Swift RS model)

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6. Diagnosis 6.1 DLC DLC is in compliance with SAE J1962 in its installation position, the shape of connector and pin assignment. OBD CAN High line and Low line (CAN line of ISO 15765-4) are used for SUZUKI scan tool (SUZUKI-SDT) or CAN communication OBD generic scan tool to communicate with ECM.

In vehicles equipped with the K-line communication system. Pin number 7 or the DLC is used for communication with the relevant control module e.g. the 4WD control module of the Suzuki Grand Vitara uses the K-line system for diagnosis by the SDT.

6.2 Measurement options The following measurement options can be used for diagnosis of the CAN bus system: • CAN data transmission test using the oscilloscope. • Voltage measurements using a voltmeter. • Terminating resistance measurements using ohmmeter.

6.2.1 Terminating resistance measurements The terminating resistor can be measured using a digital multimeter. Two 120Ω resistors are installed on either ends of the CAN bus. The total resistance of these terminating resistors is 60Ω as they are connected in parallel. Any resistance values other than 55Ω…..65Ω indicate a fault in the CAN system. 6.2.2 Voltage measurements The volt function of the digital multimeter can be used to measure the voltage levels of the CAN_H and CAN_L wires. Triggering of the digital multimeter takes place at the CAN reference level. With the ignition ON, the following voltages are measured:

Figure 13: DTC (LHD model shown)

[1] DLC location [2] B+ power supply [3] CAN_L line (Class C CAN) [4] ECM ground (signal ground) [5] Chassis ground [6] CAN_H line (Class C CAN) [7] SDT

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CAN_H (DLC pin 6) = 2.5V CAN_L (DLC pin 14) = 2.5V If the voltages are as mentioned above, the data wires are in good order and the recessive voltage is present. The measurements does not, however provide information on whether data is being transmitted in the CAN bus system. In order to determine whether dominant data signals are present in the bus system, an oscilloscope must be used.

6.2.3 Measurement using the oscilloscope Reference voltage of both CAN High signal and CAN Low signal is 2.5 V. Waveform of CAN High signal is 2.5 –3.5 V and that of CAN Low signal is 2.5 – 1.5 V.

Figure 14: Normal waveform of CAN bus system

[A] Ground level of each channel [B] Volt/div of each channel [C] Time/div of each channel [D] Waveform of channel 1 (CAN high signal) [E] Waveform of channel 2 (CAN low signal)

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• The LIN bus system was developed for use where the speeds of the CAN bus system are not necessary.

• The LIN bus system comprises of a LIN master and LIN slaves.

• The LIN slaves can include sensors or actuators or electronic control modules.

• A LIN message frame is made up of a message header and a message response.

• The UART bus system is used for communication between the keyless start system and the steering lock in the Kizashi and the Swift (AZH models).

• Measurements of the CAN bus system can be performed using an oscilloscope, voltmeter or ohmmeter.

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Reference The following abbreviations can be used in this training manual A A/B Air Bag ABDC After Bottom Dead Center ABS Anti-lock Brake System AC Alternating Current A/C Air Conditioning A-ELR Automatic-Emergency Locking Retractor A/F Air Fuel Ratio ALR Automatic Locking Retractor API American Petroleum Institute APP Accelerator Pedal Position A/T Automatic Transmission, Automatic Transaxle ATDC After Top Dead Center ATF Automatic Transmission Fluid, Automatic Transaxle Fluid AWD All Wheel Drive B BARO Barometric Pressure BBDC Before Bottom Dead Center BCM Body electrical Control Module BTDC Before Top Dead Center B+ Battery Positive Voltage BB+ Battery Positive Voltage for Backup

C CAN Controller Area Network CKP Crankshaft Position CMP Camshaft Position CO Carbon Monoxide CO2 Carbon Dioxide CPP Clutch Pedal Position CPU Central Processing Unit CVT Continuously Variable Transmission, Continuously Variable Transaxle D DC Direct Current D/C Driving Cycle DLC Data Link Connector DOHC Double Over Head Camshaft DOJ Double Offset Joint DOT Department of Transportation DPF® Diesel Particulate Filter DRL Daytime Running Light DTC Diagnostic Trouble Code (Diagnostic Code) D/C Driving Cycle

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E EBD Electronic Brake Force Distribution ECM Engine Control Module ECT Engine Coolant Temperature ECU Electronic Control Unit EEPROM Electrically Erasable Programmable Read Only Memory EFE Heater Early Fuel Evaporation Heater EGR Exhaust Gas Recirculation EGT Exhaust Gas Temperature ELR Emergency Locking Retractor ENG A-Stop Engine Auto Stop Start EPS Electronic Power Steering ESP® Electronic Stability Program EVAP Evaporative Emission G GND Ground GPS Global Positioning System H HVAC Heating, Ventilating and Air Conditioning HC Hydrocarbons HFC Hydro Fluorocarbon HI High HO2S Heated Oxygen Sensor

I IAC Idle Air Control IAT Intake Air Temperature IMT Intake Manifold Tuning ISC Idle Speed Control ISO International Organization for Standardization J JIS Japanese Industrial Standards J/B Junction Block J/C Junction Connector L L Left LCD Liquid Crystal Display LED Light Emitting Diode LHD Left Hand Drive vehicle LIN Local Interconnect Network LO Low LSPV Load Sensing Proportioning Valve M MAF Mass Air Flow MAP Manifold Absolute Pressure Max Maximum MFI Multiport Fuel Injection Min Minimum MIL Malfunction Indicator Lamp (“CHECK ENGINE” Light or “SERVICE ENGINE SOON” Light) M/T Manual Transmission, Manual Transaxle

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N NOx Nitrogen Oxides O OBD On-Board Diagnostic system OCM Occupant Classification Module OCV Oil Control Valve O/D Overdrive OHC Over Head Camshaft O2S Oxygen Sensor P PCM Powertrain Control Module PCV Positive Crankcase Ventilation PM Particulate Mater PNP Park / Neutral Position P/S Power Steering PSP Power Steering Pressure R R Right RAM Random Access Memory RHD Right Hand Drive Vehicle ROM Read Only Memory RPM Engine Speed S SAE Society of Automotive Engineers SDM Sensing and Diagnostic Module (Air Bag Controller, Air bag Control Module) SDT Smart Diagnostic Tester SFI Sequential Multiport Fuel Injection SI System International SOHC Single Over Head Camshaft SRS Supplemental Restraint System

T TCC Torque Converter Clutch TCM Transmission Control Module TCSS Traction Control Support System TDC Top Dead Center TP Throttle Position TPMS Tire Pressure Monitoring System TWC Three-Way Catalytic converter U UART Universal Asynchronous Receiver / Transmitter USB Universal Serial Bus V VFD Vacuum Fluorescent Display VIN Vehicle Identification Number VSS Vehicle Speed Sensor VVT Variable Valve Timing W WU-OC Warm Up Oxidation Catalytic converter WU-TWC Warm Up Three-Way Catalytic converter Other 2WD 2-Wheel Drive 4WD 4-Wheel Drive Note: ESP is a trademark of Daimler AG DPF® is a trademark of HJS Fahrzeugtechnik GmbH & Co KG and Suzuki is the trade mark licensee.

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Well done, you have now completed the “CS03 Communication bus

systems” online training course!

Please take the online exam

CS02 Control Systems I Body Electrical 33