Electronic & Computer Controlled Systems Course 673 Technician Handbook © 2009 Toyota Motor Sales, U. TOYOTA Technical Training All rights reserved. This book may not be reproduced or copied, in whole or in part by any means, without the written permission of Toyota Motor Sales, U. Revision Date: June 22, 2009 Table of Contents 673 Electronic & Computer Controlled Systems Objectives Final Student Performances.
a Section 1: Course Menu. 3 Diagnostic Section 1 Topics. 5 Techniques and Electronic Control Units. 6 Tools How ECUs Work.
7 Simple ECU Inputs. 8 Voltage ON/OFF (Switch) Input. 9 Variable Voltage Input. 10 Variable Resistance Input.
11 Pulse Pattern Input. 12 Simple ECU Outputs. 13 Transistors as Switches. 13 Pulse Width Modulation.
15 Power-Side Control. 17 Differences in Self-Diagnosis. 19 Types of ECU Memory. 21 Section 2: Section 2 Topics.
23 Overview of Why Use Multiplexing. 24 Multiplex Applications of Multiplexing. 24 Communication Benefits of Multiplexing. 26 Signaling Between ECUs.
30 Two Opens in a Ring Network. 31 Open in a Star Network. 32 Open in a Bus Network. 33 Single Wire vs.
34 Advantage of Twisted-Pair Wiring. 35 Section 3: Section 3 Topics. 37 Signals & Electronic Communication. 38 Waveforms Types of Waveforms.
39 Technical Training i Table of Contents 673 Electronic & Computer Controlled Systems Frequency. 42 Section 4: Section 4 Topics. 43 Measuring The Oscilloscope. 44 Signals PC Oscilloscopes.
47 Repair Manual Suggested Scales. 50 Scope Pattern Comparison. 51 The Effect of Scale. 53 Other Trigger Uses.
54 Advanced DVOM Features. 55 MIN/MAX Recording. 55 Peak MIN/MAX. 56 Worksheet: DVOM Set-up & Advance Features.
57 Instructor Demo: Using DVOM Resistance Setting. 58 Section 5: Using Section 5 Topics. 59 a PicoScope™ Introduction to PicoScope™. 60 Connecting the Leads.
61 Auto Voltage Scale. 61 Manual Voltage Scale Settings. 62 Manual Time Scale Settings. 62 Turning the Trigger On.
63 Setting the Trigger. 64 Start and Stop Capturing. 69 Displaying Two Channels. 70 Separating the A-B Traces.
71 Printing, Saving and Sending Patterns. 72 Worksheet: In-class PicoScope: Basic Set-up. 73 Worksheet: Using DVOM & PicoScope. 74 Instructor Demo: PicoScope & Power Window Circuit.
74 ii Technical Training Table of Contents 673 Electronic & Computer Controlled Systems Section 6: Using Section 6 Topics. 75 an Inductive The Inductive Clamp. 77 Preparation for Use. 78 Converting Measurements to Amps.
79 Amp Clamp Applications. 80 Diagnosing Short Circuits and Parasitic Draw. 80 Diagnosing Motor Faults with an Oscilloscope. 81 Worksheet: Inductive Current Clamp I: Measurement & Conversion.
82 Worksheet: Inductive Current Clamp II: A/C Blower Motor. 82 Section 7: Section 7 Topics. 83 Multiplex Circuit Additional Properties of MPX Protocols. 84 Diagnosis Communication Direction.
89 Body Electronics Area Network. 90 Local Interconnect Network. 91 LIN Replacing BEAN. 91 LIN Gateway Function.
92 Controller Area Network. 93 Audio Visual Communication-Local Area Network. 94 AVC-LAN Protocol. 96 CAN Gateway ECU.
96 Summary of Gateway ECU Functions. 97 CAN Gateway ECU Functions. 98 Transmit/Receive Charts. 103 Short Circuit Step 1.
104 Short Circuit Step 2. 105 Short Circuit Step 3. 106 Short Circuit Step 4. 107 Short Circuit Step 5.
108 Short Circuit Step 6. 109 Diagnosing a Large Network. 110 Diagnosing with Techstream. 111 Diagnosing a BEAN Open Circuit with an Oscilloscope.
112 Technical Training iii Table of Contents 673 Electronic & Computer Controlled Systems Worksheet: BEAN Network Diagnosis. 113 Instructor Demo: BEAN Operation and Diagnosis. 115 Worksheet: A/C LIN Interface. 118 Short Between CANH and CANL.
118 Short to B+ or Ground. 119 CAN Bus Check. 120 Location of DLC3. 121 Resistance Tests on CAN Circuits.
122 Worksheet: CAN Diagnosis. 124 Instructor Demo: CAN Resistance Test Precautions. 124 Worksheet: CAN Main Bus Faults. 125 Worksheet: CAN Sub Bus Diagnosis.
125 AVC-LAN Signal. 126 AVC-LAN Diagnosis. 127 AVC-LAN DTCs. 128 Worksheet: AVC-LAN Inspection.
129 Other Multiplex Circuits. 130 A/C Servo Motor Circuits. 131 Pulse-Type Servo Motors. 132 Worksheet: A/C Bus Servo Motor Operation & Diagnosis.
133 Section 8: Section 8 Topics. 135 Electronic Engine Immobilizer Function. 136 Systems Engine Immobilizer Operation. 137 Key Code Registration.
137 Master Keys and Sub Keys. 138 Automatic Key Code Registration. 139 Watch for Error Codes. 139 Ending Automatic Registration.
139 Configuration in Earlier Models. 140 Configuration in Later Models. 142 Immobilizer Reset Support Chart. 143 ECU Communication ID Registration.
144 Be Wary of Differences between Models. 145 Analyzing ECU Input and Outputs. 147 Power and Ground Circuits. 148 Terminal Values and Conditions.
149 iv Technical Training Table of Contents 673 Electronic & Computer Controlled Systems Transponder Key Amplifier Terminal Values. 150 ECM Terminal Values. 153 Mode Monitor Terminal. 153 Smart Junction Box (MICON).
154 High Intensity Discharge (HID) Headlights. 155 Dynamic Laser Cruise Control Operation. 158 Error/Cancellation Codes. 158 Constant Speed Control.
160 Follow-Up Control. 163 Distance Control ECU Waveforms. 164 Laser Radar Sensor Waveforms. 169 How a Transistor Works.
173 Analog-to-Digital Converter. 175 Normal CAN Signal. 176 CAN Shorts and Opens. 177 Short CANH to CANL.
177 Short CANH to B+. 178 Short CANL to B+. 178 Short CANH to Ground. 179 Short CANL to Ground.
179 Open in CANH or CANL (Main Bus). 180 Open in CANH and CANL (Main Bus). 182 BEAN Short to Ground. 183 Normal BEAN, Dual Trace.
184 BEAN Open Circuit, Dual Trace. 185 Worksheets Technical Training v Table of Contents 673 Electronic & Computer Controlled Systems This page intentionally left blank. vi Technical Training Objectives 673 Electronic & Computer Controlled Systems Course 673 Electronic & Computer Controlled Systems Final Student Performances Terminal Objective (Terminal FSP) Given all of the applicable tools, equipment, and appropriate vehicles, the technician will be able to apply a number of diagnostic techniques to monitor and repair faults in advanced computer and electronic circuits. Technician Objectives (FSPs) The technician will be able to: 1.
Research information related to: • The purpose and function of ECU terminals • Inputs & Outputs • Terminals of the ECU • Power & Ground points 2. Identify inputs and outputs and determine how they affect ECU operation. Differentiate between: • Pulse width & duty cycle • Frequency & duty cycle 4. Identify the consequences of the following to the diagnostic process: • Initialization (Memory Loss) • Customization (CBEST) • Sleep mode vs.
Demonstrate proficient use of the advanced DVOM features. • MIN/MAX function • Peak MIN/MAX function • Measure frequency • Measure duty cycle 6. Apply advanced DVOM functions for quick diagnostic evaluations. Practice using an Inductive Current Clamp with a DVOM to provide the ability to take current readings without breaking into a circuit.
Utilize an inductive Current Clamp to evaluate system operation & determine diagnostic strategy. Practice conversion of voltage and amperage values to apply to inductive clamps that use conversion factors for sensitivity. Monitor AC blower motor current using a DVOM equipped with an inductive current clamp, and monitor current using an oscilloscope and inductive clamp. Technical Training a Objectives 673 Electronic & Computer Controlled Systems 11.
Properly set-up an oscilloscope • Auto features • Voltage & Time Scale Settings • Horizontal & vertical rulers • Trigger point • Horizontal & vertical zoom features 12. Apply the basic features of the oscilloscope used in combination with the Techstream Unit. Locate and back probe a dimmer-controlled interior lamp or LED, practice measuring Voltage (V), Hertz (Hz), and percentage values (%) using a DVOM, and use an oscilloscope to display the signal pattern. Set oscilloscope voltage and time settings appropriate to the circuit measured.
Utilize oscilloscope patterns derived from a known good vehicle to verify normal system operation. Differentiate between different oscilloscope patterns. Use an oscilloscope to confirm proper operation vs. a faulty circuit • Duty cycle • Frequency • Amplitude 18.
Use an oscilloscope to identify intermittent faults. Capture, record, save and send oscilloscope waveforms. Identify Body Electronics Area Network topology and network operation. Perform fault diagnostics on a BEAN network.
Identify Local Area Network topology and network operation. Monitor and diagnose the AC Control Assembly operation and LIN communication using Techstream, an oscilloscope and TIS. Identify Controller Area Network topology and network operation. Use an ohmmeter and an oscilloscope to observe CAN High and CAN Low; diagnose a short to ground and an open circuit on CAN High and CAN Low; and short CAN High to CAN Low to observe the results.
Develop a strategy to diagnose a CAN Network fault using the EWD, a Techstream CAN Bus Check, and the information provided. Identify Audio Visual Communication-Local Area Network topology and network operation. Create, monitor and diagnose an AVC-LAN System amplifier malfunction using Techstream and an oscilloscope. Monitor AC bus and servo motor operation using Techstream DATA LIST and an oscilloscope to deduce communication problems with the AC System.
Reference service literature to determine if immobilizer reset is supported on a vehicle. Use Techstream Data List to make determinations related to the ID Code of the transponder chip embedded in the ignition key of the Immobilizer System. Use an oscilloscope to observe Immobilizer System waveforms under varying conditions and compare them to those found in the Repair Manual. b Technical Training 673 Electronic & Computer Controlled Systems Technician Handbook 673 Electronic & Computer Controlled Systems Welcome Toyota Technicians Technical Training 1 673 Electronic & Computer Controlled Systems Technician Handbook This Page Intentionally Left Blank 2 Technical Training 673 Electronic & Computer Controlled Systems Technician Handbook Course Menu Electronic & Computer Controlled Systems • Electronic Control Units • Overview of Multiplex Communication • Signals & Waveforms • Measuring Signals • Using a PicoScope™ • Using an Inductive Clamp • Multiplex Circuit Diagnosis • Electronic Systems • Transistors A Appendix • CAN Waveforms • BEAN Waveforms Technical Training 3 673 Electronic & Computer Controlled Systems Technician Handbook This Page Intentionally Left Blank 4 Technical Training 673 Electronic & Computer Controlled Systems Technician Handbook Section 1 Topics Electronic Control Units • Electronic Control Units • Logic Function • Simple ECU Inputs • Simple ECU Outputs • Self-Diagnosis • Memory • Customization • Initialization Technical Training 5 673 Electronic & Computer Controlled Systems Technician Handbook Electronic Control Units Electronic Control Units (ECUs) are small computers programmed to perform specific automotive functions.
What are some typical automotive ECUs? ECUs use electronic components in integrated circuits to perform their functions. Electronic In the 1970’s, the decreasing cost and increasing power of computerized Control Units microprocessors launched the personal computer industry. Because of their speed and flexibility in carrying out complex functions, microprocessors were adapted for hundreds of uses beyond personal computers. The first microprocessors began appearing in automotive engine control systems in the early 1980s.
In automotive applications, they became known as electronic control units (ECUs). Today, some vehicles may have dozens of ECUs controlling a wide variety of vehicle systems, including: • engine controls • transmission • braking • steering • air conditioning • door locks • suspension • cruise control • tire pressure monitoring • and many other systems. 6 Technical Training 673 Electronic & Computer Controlled Systems Technician Handbook ECU Logic Function ECUs have electronic logic circuits that “make decisions” by evaluating conditions according to predetermined rules.