Diagnosis and troubleshooting of automotive electrical презентация

Содержание

OBJECTIVES After studying Chapter 38, the reader will be able to: Prepare for ASE computerized engine controls diagnosis (A8) certification test content area “E.” List the steps of the diagnostic process.

Слайд 2OBJECTIVES
After studying Chapter 38, the reader will be able to:
Prepare for

ASE computerized engine controls diagnosis (A8) certification test content area “E.”
List the steps of the diagnostic process.
Describe the simple preliminary tests that should be performed at the start of the diagnostic process.
List six items to check as part of a thorough visual inspection.

Слайд 3OBJECTIVES
Explain the troubleshooting procedures to follow if a diagnostic trouble code

has been set.
Explain the troubleshooting procedures to follow if no diagnostic trouble code has been set.
Discuss the type of scan tools that are used to assess vehicle components.
Describe the methods that can be used to reprogram (reflash) a vehicle computer.

Слайд 4THE EIGHT-STEP DIAGNOSTIC PROCEDURE
It is important that all automotive service technicians

know how to diagnose and troubleshoot engine computer systems.
The diagnostic process is a strategy that eliminates known-good components or systems in order to find the root cause of automotive engine performance problems.
All vehicle manufacturers recommend a diagnostic procedure, and the plan suggested in this chapter combines most of the features of these plans plus additional steps developed over years of real-world problem solving.

Слайд 5THE EIGHT-STEP DIAGNOSTIC PROCEDURE
Verify the Problem (Concern)
Perform a Thorough Visual Inspection

and Basic Tests
Check for obvious problems (basics, basics, basics).
Check everything that does and does not work.
Look for evidence of previous repairs.
Check oil level and condition.
Check coolant level and condition.
Use the paper test
Ensure adequate fuel level.
Check the battery voltage.
Check the spark using a spark tester.
Check the fuel pump pressure

Слайд 6THE EIGHT-STEP DIAGNOSTIC PROCEDURE
Retrieve the Diagnostic Trouble Codes (DTCs)
Check for Technical

Service Bulletins (TSBs)
Look Carefully at Scan Tool Data
Narrow the Problem to a System or Cylinder
Repair the Problem and Determine the Root Cause
Verify the Repair and Clear Any Stored DTCs

Слайд 7THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-1 A funnel is one way to

visualize the diagnostic process. The purpose is to narrow the possible causes of a concern until the root cause is determined and corrected.

FIGURE 38-2 Step #1 is to verify the customer concern or problem. If the problem cannot be verified, then the repair cannot be verified.


Слайд 8THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-3 A form that the customer should

fill out if there is a driveablilty concern to help the service technician more quickly find the root cause.

Слайд 9THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-4 This is what was found when

removing an air filter from a vehicle that had a lack-of-power concern. Obviously the nuts were deposited by squirrels or some other animal, blocking a lot of the airflow into the engine.

Слайд 10THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-5 Using a bright light makes seeing

where the smoke is coming from easier. In this case, smoke was added to the intake manifold with the inlet blocked with a yellow plastic cap and smoke was seen escaping past a gasket at the idle air control.

Слайд 11THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-6 A spark tester connected to a

spark plug wire or coil output. A typical spark tester will only fire if at least 25,000 volts is available from the coil, making a spark tester a very useful tool. Do not use one that just lights when a spark is present, because they do not require more than about 2,000 volts to light.

Слайд 12THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-7 Step #3 in the diagnostic process

is to retrieve any stored diagnostic trouble codes.

Слайд 13THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-8 After checking for stored diagnostic trouble

codes (DTCs), the wise technician checks service information for any technical service bulletins that may relate to the vehicle being serviced.

Слайд 14THE EIGHT-STEP DIAGNOSTIC PROCEDURE
FIGURE 38-9 Looking carefully at the scan tool

data is very helpful in locating the source of a problem.

FIGURE 38-10 Step #8 is very important. Be sure that the customer’s concern has been corrected.


Слайд 15SCAN TOOLS
Scan tools are the workhorse for any diagnostic work on

all vehicles.
Scan tools can be divided into two basic groups:
Factory scan tools.
Aftermarket scan tools

Слайд 16SCAN TOOLS
FIGURE 38-11 A TECH 2 scan tool is the factory

scan tool used on General Motors vehicles.

FIGURE 38-12 Some scan tools use pocket PCs which make it very convenient to use.


Слайд 17RETRIEVAL OF DIAGNOSTIC INFORMATION
To retrieve diagnostic information from the PCM, use

the following steps:
Locate and gain access to the data link connector (DLC).
Connect the scan tool to the DLC and establish communication.
Follow the on-screen instructions of the scan tool to correctly identify the vehicle.
Observe the scan data, as well as any diagnostic trouble codes.
Follow vehicle manufacturer’s instructions if any DTCs are stored. If no DTCs are stored, compare all sensor values with a factory acceptable range chart to see if any sensor values are out-of-range.

Слайд 18TROUBLESHOOTING USING DIAGNOSTIC TROUBLE CODES
Pinning down causes of the actual problem

can be accomplished by trying to set the opposite code.
For example, if a code indicates an open throttle position (TP) sensor (high resistance), clear the code and create a shorted (low-resistance) condition.
This can be accomplished by using a jumper wire and connecting the signal terminal to the 5-volt reference terminal.

Слайд 19TROUBLESHOOTING USING DIAGNOSTIC TROUBLE CODES
Methods for Clearing Diagnostic Trouble Codes


Слайд 20FLASH CODE RETRIEVAL ON OBD-I GENERAL MOTORS VEHICLES
The GM system uses

a “check engine” or “check engine soon” MIL to notify the driver of possible system failure. Under the dash (on most GM vehicles) is a data link connector (DLC) previously called an assembly line communications link (ALCL) or assembly line diagnostic link (ALDL).
Most General Motors diagnostic trouble codes can be retrieved by using a metal tool and contacting terminals A and B of the 12-pin DLC

Слайд 21FLASH CODE RETRIEVAL ON OBD-I GENERAL MOTORS VEHICLES
FIGURE 38-13 To retrieve

flash codes from an OBD-I General Motors vehicle, connect terminals A and B with the ignition on–engine off. The M terminal is used to retrieve data from the sensors to a scan tool.

Слайд 22RETRIEVING FORD DIAGNOSTIC CODES
The best tool to use during troubleshooting of

a Ford vehicle is a self-test automatic readout (STAR) tester, new generation STAR (NGS), WDS (Worldwide Diagnostic System), or another scan tool with Ford capabilities.
If a STAR tester or scan tool is not available, a needle (analog) type of voltmeter can be used for all OBD-I (prior to 1996) systems.

Слайд 23RETRIEVING FORD DIAGNOSTIC CODES
FIGURE 38-14 A Ford OBD-I self-test connector. The

location of this connector can vary with model and year of vehicle.

Слайд 24RETRIEVING FORD DIAGNOSTIC CODES
Key On–Engine Off Test (On-Demand Codes or Hard

Faults)
Separator Pulse
Continuous Memory Codes (Soft Codes)
Key On–Engine Running (KOER) Test
Steering,Brake, and Overdrive Switch Test
Dynamic Response Check

Слайд 25PUT A WIRE IN THE ATTIC AND A LIGHT IN THE

BASEMENT!

FIGURE 38-15 To retrieve Ford DTCs using a test light and a jumper wire, turn the ignition switch on (engine off) and make the connections shown. The test light will blink out the diagnostic trouble codes.


Слайд 26FLASH CODE RETRIEVAL ON CHRYSLER VEHICLES
To put the computer into the

self-diagnostic mode, the ignition switch must be turned on and off twice within a 5-second period (on-off-on-off-on).
The computer will flash a series of fault codes.
Older Chrysler brand products flash the “check engine” lamp on the dash.

Слайд 27OBD-II DIAGNOSIS
Starting with the 1996 model year, all vehicles sold in

the United States must use the same type of 16-pin data link connector (DLC) and must monitor emission-related components.
Retrieving OBD-II Codes

Слайд 28OBD-II DIAGNOSIS
FIGURE 38-16 A typical OBD-II data link connector (DLC). The

location varies with make and model and may even be covered, but a tool is not needed to gain access. Check service information for the exact location if needed.

Слайд 29OBD-II ACTIVE TESTS
OBD-II Drive Cycle
Types of OBD-II Codes
Type A Codes.
Type B

Codes.
Type C and D Codes.
OBD-II Freeze-Frame
Diagnosing Intermittent Malfunctions

Слайд 30SERVICE/FLASH PROGRAMMING
Remote Programming
Direct Programming
Off-Board Programming


Слайд 31SERVICE/FLASH PROGRAMMING
FIGURE 38-17 The first step in the reprogramming procedure is

to determine the current software installed using a scan tool. Not all scan tools can be used. In most cases using the factory scan tool is needed for reprogramming unless the scan tool is equipped to handle reprogramming.

Слайд 32SERVICE/FLASH PROGRAMMING
FIGURE 38-18 Follow the on-screen instructions.


Слайд 33SERVICE/FLASH PROGRAMMING
FIGURE 38-19 An Internet connection is usually needed to perform

updates although some vehicle manufacturers use CDs which are updated regularly at a cost to the shop.

Слайд 34SERVICE/FLASH PROGRAMMING
FIGURE 38-20 Connecting cables and a computer to perform offboard

programming.

Слайд 35J2534 REPROGRAMMING
Legislation has mandated that vehicle manufacturers meet the SAE J2534

standards for all emissions-related systems on all new vehicles starting with model year 2004.
This standard enables independent service repair operators to program or reprogram emissions-related ECMs from a wide variety of vehicle manufacturers with a single tool.

Слайд 36J2534 REPROGRAMMING
FIGURE 38-21 The J2534 pass-through reprogramming system does not need

a scan tool to reflash the PCM on most 2004 and newer vehicles.

Слайд 37J2534 REPROGRAMMING
FIGURE 38-22 A typical J2534 universal reprogrammer that uses the

J2534 standards.

Слайд 38MANUFACTURER’S DIAGNOSTIC ROUTINES
Each vehicle manufacturer has established their own diagnostic routines

and they should be followed. Most include the following steps:
Retrieve diagnostic trouble codes.
Check for all technical service bulletins that could be related to the stored DTC.
If there are multiple DTCs, the diagnostic routine may include checking different components or systems instead of when only one DTC was stored.
Perform system checks.
Perform a road test matching the parameters recorded in the freeze-frame to check that the repair has corrected the malfunction.
Repeat the road test to cause the MIL to be extinguished.

Слайд 39COMPLETING SYSTEM REPAIRS
After the repair has been successfully completed, the vehicle

should be driven under similar conditions that caused the original concern.
Verify that the problem has been corrected.
To perform this test drive, it is helpful to have a copy of the freezeframe parameters that were present when the DTC was set.
By driving under similar conditions, the PCM may perform a test of the system and automatically extinguish the MIL.

Слайд 40PROCEDURES FOR RESETTING THE PCM
The PCM can be reset or cleared

of previously set DTCs and freeze-frame data in the following ways:
Driving the Vehicle.
Clear DTCs Using a Scan Tool.
Battery Disconnect.

Слайд 41ROAD TEST (DRIVE TRACE)
Use the freeze-frame data and test-drive the vehicle

so that the vehicle is driven to match the conditions displayed on the freezeframe.
If the battery has been disconnected, then the vehicle may have to be driven under conditions that allow the PCM to conduct monitor tests
Universal Drive Cycle

Слайд 42EUROPEAN BOSCH DIAGNOSIS
Diagnosing a European brand vehicle, such as a Volkswagen,

Audi, Mercedes, or BMW, can be a challenge.
One of the challenges is that global (generic) scan tools, while capable of supplying the specified data, do not allow access to many diagnostic trouble codes that might be set and stored.
Using factory-level scan tools, such as VAG-COM, launch X431, or Baum iscan, results in some terms that are not familiar such as:
Address word.
Function
Display group
Using Function 04

Слайд 43SUMMARY
Funnel diagnostics—Visual approach to a diagnostic procedure:
Verify the problem (concern)
Perform a

thorough visual inspection and basic tests
Retrieve the diagnostic trouble codes (DTCs)
Check for technical service bulletins (TSBs)
Look carefully at scan tool data
Narrow the problem to a system or cylinder
Repair the problem and determine the root cause
Verify the repair and check for any stored DTCs
Care should be taken to not induce high voltage or current around any computer or computer-controlled circuit or sensor.
A thorough visual inspection is important during the diagnosis and troubleshooting of any engine performance problem or electrical malfunction.
If the MIL is on, retrieve the DTC and follow the manufacturer’s recommended procedure to find the root cause of the problem.
OBD-II vehicles use a 16-pin DLC and common DTCs.

Слайд 44REVIEW QUESTIONS
Explain the procedure to follow when diagnosing a vehicle without

any stored DTCs using a scan tool.
Discuss what the PCM does during a drive cycle to test emission-related components.
Explain the difference between a type A and type B OBD-II diagnostic trouble code.
List three things that should be checked as part of a thorough visual inspection.
List the eight-step funnel diagnostic procedure.
Explain why a bulletin search should be performed after stored DTCs are retrieved.
List the three methods that can be used to reprogram a PCM.

Слайд 45CHAPTER QUIZ
Technician A says that the first step in the diagnostic

process is to verify the problem (concern). Technician B says the second step is to perform a thorough visual inspection. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 46CHAPTER QUIZ
Technician A says that the first step in the diagnostic

process is to verify the problem (concern). Technician B says the second step is to perform a thorough visual inspection. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 47CHAPTER QUIZ
2. Which item is not important to know before starting the

diagnosis of an engine performance problem?
List of previous repairs
The brand of engine oil used
The type of gasoline used
The temperature of the engine when the problem occurs

Слайд 48CHAPTER QUIZ
2. Which item is not important to know before starting the

diagnosis of an engine performance problem?
List of previous repairs
The brand of engine oil used
The type of gasoline used
The temperature of the engine when the problem occurs

Слайд 49CHAPTER QUIZ
3. A paper test can be used to check for a

possible problem with _____.
The ignition system (bad spark plug wire)
A faulty injector on a multiport engine
A burned valve
All of the above

Слайд 50CHAPTER QUIZ
3. A paper test can be used to check for a

possible problem with _____.
The ignition system (bad spark plug wire)
A faulty injector on a multiport engine
A burned valve
All of the above

Слайд 51CHAPTER QUIZ
4. Which step should be performed last when diagnosing an engine

performance problem?
Checking for any stored diagnostic trouble codes
Checking for any technical service bulletins (TSBs)
Performing a thorough visual inspection
Verify the repair

Слайд 52CHAPTER QUIZ
4. Which step should be performed last when diagnosing an engine

performance problem?
Checking for any stored diagnostic trouble codes
Checking for any technical service bulletins (TSBs)
Performing a thorough visual inspection
Verify the repair

Слайд 53CHAPTER QUIZ
5. Technician A says that if the opposite DTC can be

set, the problem is the component itself. Technician B says if the opposite DTC cannot be set, the problem is with the wiring or grounds. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 54CHAPTER QUIZ
5. Technician A says that if the opposite DTC can be

set, the problem is the component itself. Technician B says if the opposite DTC cannot be set, the problem is with the wiring or grounds. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 55CHAPTER QUIZ
6. The preferred method to clear diagnostic trouble codes (DTCs) is

to _____.
Disconnect the negative battery cable for 10 seconds
Use a scan tool
Remove the computer (PCM) power feed fuse
Cycle the ignition key on and off 40 times

Слайд 56CHAPTER QUIZ
6. The preferred method to clear diagnostic trouble codes (DTCs) is

to _____.
Disconnect the negative battery cable for 10 seconds
Use a scan tool
Remove the computer (PCM) power feed fuse
Cycle the ignition key on and off 40 times

Слайд 57CHAPTER QUIZ
7. Which is the factory scan tool for Chrysler brand vehicles

equipped with CAN?
Star Scan
Tech 2
NGS
Master Tech

Слайд 58CHAPTER QUIZ
7. Which is the factory scan tool for Chrysler brand vehicles

equipped with CAN?
Star Scan
Tech 2
NGS
Master Tech

Слайд 59CHAPTER QUIZ
8. Technician A says that reprogramming a PCM using the J2534

system requires a factory scan tool. Technician B says that reprogramming a PCM using the J2534 system required Internet access. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 60CHAPTER QUIZ
8. Technician A says that reprogramming a PCM using the J2534

system requires a factory scan tool. Technician B says that reprogramming a PCM using the J2534 system required Internet access. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 61CHAPTER QUIZ
9. Technician A says that knowing if there are any stored

diagnostic trouble codes (DTCs) may be helpful when checking for related technical service bulletins (TSBs). Technician B says that only a factory scan tool should be used to retrieve DTCs. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 62CHAPTER QUIZ
9. Technician A says that knowing if there are any stored

diagnostic trouble codes (DTCs) may be helpful when checking for related technical service bulletins (TSBs). Technician B says that only a factory scan tool should be used to retrieve DTCs. Which technician is correct?
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B

Слайд 63CHAPTER QUIZ
10. Which method can be used to reprogram a PCM?
Remote
Direct
Off-board
All of

the above

Слайд 64CHAPTER QUIZ
10. Which method can be used to reprogram a PCM?
Remote
Direct
Off-board
All of

the above

Обратная связь

Если не удалось найти и скачать презентацию, Вы можете заказать его на нашем сайте. Мы постараемся найти нужный Вам материал и отправим по электронной почте. Не стесняйтесь обращаться к нам, если у вас возникли вопросы или пожелания:

Email: Нажмите что бы посмотреть 

Что такое ThePresentation.ru?

Это сайт презентаций, докладов, проектов, шаблонов в формате PowerPoint. Мы помогаем школьникам, студентам, учителям, преподавателям хранить и обмениваться учебными материалами с другими пользователями.


Для правообладателей

Яндекс.Метрика