Presentation on theme: "NEXTECH and Carman Scan VG Your Partners for the Road Ahead!"— Presentation transcript:
1 NEXTECHandCarman Scan VGYour Partners for the Road Ahead!
2 What is the advantage of a Combination Data Scanner / Oscilloscope over a basic Data Scanner?A basic Data Scanner can perform the following functions:Read and Erase Fault codesDisplay Current Data to verify a fault exists.Perform Actuation tests.However, determining whether a fault is caused by a component failure, a wiring fault or a faulty ECM requires more than just a Scanner.The Carman Scan 1 and Carman Scan VG provide the technician with a complete solution for Diagnostics.
3 The use of an Oscilloscope is a necessity for pinpointing vehicle faults.During the course we will be studying the operation of the VG as well as the correct procedures required for testing a numberof common components.
4 THE CARMAN SCAN VG TRAINING COURSE #1 OSCILLOSCOPE TRAINING
6 Hz % m/s VOLTAGE TIME 8v 6v 4v 2v 0v Hz = Frequency (Number of Pulses per second).% = Duty Cycle (On/Off Ratio).m/s = Time measurement.
7 The Lab Scope is one of the most valuable diagnostic tools available to the modern workshop today.It is commonly used to check:Supply voltageVoltage Drops (in power and earth circuits).AC WaveformsDC Waveforms (Square waves etc.)Pulse Signals
8 + v 0 v - v TYPICAL AC WAVEFORM AC Waveforms are generated from such devices as:Alternators (before rectification)Crank Angle SensorsTDC SensorsVehicle Speed SensorsTransmission Pulse Generators
9 5 v 0 v 5 v 0 v TYPICAL SQUARE WAVEFORM OFF ON ON OFF GROUND SWITCHEDSIGNALDuty Cycle 50%0 vONON5 vPOSITIVELY SWITCHEDSIGNALDuty Cycle 50%0 vOFFSquare Waveforms are commonly used for inputs such as:Crank Angle Sensors, Camshaft Sensors, TDC Sensors,Vehicle Speed Sensors, MAP Sensors (Ford),Air Flow Sensors or outputs such as Idle Speed Control Motors
18 Select the number of cylinders to be tested. Selecting Secondary IgnitionSelect the number of cylinders to be tested.
19 Select the type of Ignition and the approximate idle speed. Selecting Secondary Ignition typeSelect the type of Ignition and the approximate idle speed.
20 Select the correct firing order from the list or make a Selecting Secondary Ignition firing orderSelect the correct firing order from the list or make anew one using the numbers in “other”.
21 Selecting Secondary Ignition Probe Type Press “SAVE” when completedSelect the correct probe. E.g. “1 to1” when using a single probe,or “1 to 3” / “1 to 4” for Multi-Probes (DLI Ignition etc.)
22 Special Note: DLI Vehicles Conventional Ignition vehicles are normally “Negative” firing,and, therefore, the spark plugs fire from the centre electrode to theouter electrode of the plug.On DLI, Waste Spark vehicles, half of the cylinders are “Negative”firing, and therefore fire from the centre electrode to the outerelectrode of the spark plug, whilst the other half of the cylinders(their mating cylinders) are “Positive”, firing from theouter electrode to the centre electrode.Please refer to the following diagram.
23 Distributor-less Ignition Operation Electron Flow
24 Conventional Ignition When connecting the VG to a conventional Ignition Vehicle, theSecondary Ignition pickup lead is connected to Channel 2 of theVG and the #1 Trigger lead is connected to Channel 3DLI Waste Spark IgnitionWhen connecting the VG to a DLI Vehicle, the “Positive” cylindersare connected to Channel 1 and the “Negative” cylinders, connectedto Channel 2. The #1 Trigger lead is connected to Channel 3 as usual.
25 Determining the Positive and Negative firing cylinders If unsure which cylinders are Positive firing and which areNegative firing, simply take ONE secondary pickup lead andconnect it to Channel 1 or Channel 2 of the VG.With the engine running, place the secondary pickup lead aroundone cylinder at a time. Any cylinders that produce an ignitionpattern facing up the correct way on the scope are the correctPolarity for that channel.Any cylinders displaying an upside down pattern are incorrectpolarity and therefore belong the the other Channel.Please refer to the following diagrams.
26 Correct Polarity for the channel selected. Note, the Ignition pattern is displayed the correct way up.
27 Incorrect Polarity for the channel selected. Connect this Cylinder to the other channel.Incorrect Polarity.Note, the Ignition pattern is displayed upside down.
28 Demonstration here of determining correct Polarity
29 SPLIT SCREEN (Default Screen) = Parade + Single Cylinder Note: This is a Waste Spark DIS vehicle.Mating Cylinders are: 1&4; 3&6; 5&2.
31 Screen SettingsSets the “Voltage Scale” for the Parade and Single Cylinder Patterns.Sets the “Time Base” for the Parade Pattern only.Sets the “Trigger Level”. Adjust whenever Patterns are erratic orCylinder #’s are erratic or missing.Allows the user to select which Single Cylinder will be displayed on the screen.Allows the screen to be changed to display the patterns as either:“Series”(Parade), “Single Cylinder”, “Trend Plot” or “3D”.Turns the “Information” display on or off.
32 Demonstration here of effects of incorrect Trigger level
33 Selecting a new “Single Cylinder” to be displayed To Select a new single cylinder, press “CYLINDER”, then press the cylinder #
34 Selecting a new “Single Cylinder” #6 SelectedTo Select one of the other two cylinders, press “MORE”.
35 Selecting a new “Single Cylinder” #3 SelectedSelecting other Cylinders for display.
36 Demonstration here of Selecting a New Single Cylinder for Display
54 “Split Screen” with open circuit HT lead on # 5 Cylinder High Burn KV.Note: High Burn KV shown above.
55 “Series Screen” with open circuit HT lead on # 5 Cylinder High Peak KVHigh Burn KVAlso note faulty pattern on #2 Cylinder (DIS mating cylinder for #5)
56 “Single Cylinder” with open circuit HT lead on # 5 Cylinder Note: High Peak Volts, High Burn Volts and Short Burn Time.
57 “Trend Plot” with open circuit HT lead on # 5 Cylinder High Peak KVHigh Peak KVHigh Peak KVShort Burn TimeHigh Burn KVNote High Peak Voltage, High Burn Voltage and Low Burn Timeon cylinders 5 and 2
58 “3D Screen” with open circuit HT lead on # 5 Cylinder Note High Peak KV, High Burn KV and Short Burn Time onCylinders 5 and 2
59 Other Faulty Ignition Patterns High Resistance in HT Lead(High Negative Slope, with normal peak KV)Fouled Spark Plug or HT Leakage(High Negative Slope, with low peak KV)Lean Cylinder under Acceleration(High Positive Slope, under load)
61 Oscilloscope Operation VG LABSCOPEFor the remainder of the course, all waveforms will be displayed live on your VG. Please follow setup screens as shown on the following slides.
62 Selecting Lab ScopeTouch the “OSCILLOSCOPE” Icon.
63 Selecting Auto SetupTouch the“Auto Setup” Icon.
64 Selecting Auto SetupSelect the type of signal to be tested and the channelto be used.
65 After selecting the type of signal and the channel press Selecting Auto SetupPress “SAVE” when completedAfter selecting the type of signal and the channel press“SAVE” to progress to Lab Scope screen.
66 Testing Crankshaft Position Sensors (Hall type) – Engine idling 20 m/s time-base is set for testing during “crank” conditions.If testing with the engine running reduce the time base.To change the time-base, touch the side arrows or select “SET TIME”
67 Testing Crankshaft Position Sensors (Hall type) – Engine idling To change the voltage level, touch the up/down arrows or select “SET VOLT”
68 Testing Crankshaft Position Sensors (Hall type) Voltage scale set to 2v (per division)Time-base adjusted to 2 m/s (per division) for testing withthe engine running.Cylinder ID Signal.Typical Crank Angle Sensor signal at idle.
69 Changing the Screen Settings. Changing the Screen settings: To change the screen settings touch “SCREEN”
70 Changing the Screen Settings. Changing the Screen settings: “Waveform only” Screen selected
71 Changing the Screen Settings. Digital readings displayedChanging the Screen settings: “Digital Display” Screen selected
72 Changing the Screen Settings. Changing the Screen settings: To change grid settings touch “GRID”
73 Changing the Screen Settings. To change the grid settings, select one of the above on the left.
74 Changing the Screen Settings. To remove the grid (as seen above), touch
75 Changing the Screen Settings. To display quarter grid (as seen above), touch
81 Faulty Crank Angle Sensor Signal during crank. At first glance this pattern looks quite normal, however, if you study it closely you will see it’sdefinitely not normal.Problem was caused by a faulty Crank Angle SensorApprox 1.0vGround = 0vThe vehicle here would not start as the hall sensor failed to switch the signal fully to ground (0v). Because of this, the ECM would not fire the Ignition.
82 Faulty Sensor signal captured on Carman Scan 1 Duty cycle varying.(Should have been aconstant 50% duty cycleon this vehicle)The uneven duty cycle resulted in dramatic ignition timing problems, causingbackfiring, misfiring and impossible driving conditions.Problem was caused by a “brand new” faulty Crank Angle Sensor.
83 Recording Please Note: 1. The VG is always “recording” whilst in the Lab Scope mode.2. To end the recording, Press “STOP”.3. If ‘STOP” is pressed before the full record time has elapsed, theVG will display a message to say it is “saving data, please wait”4. The length of the record time will depend on the time baseselected.
87 Replaying recorded waveforms Progression indicator.To replay the waveforms, Press the left arrow.
88 Recording waveforms To Pause the waveforms, Press the Pause. Waveform Paused.To Pause the waveforms, Press the Pause.
89 Recording waveformsTo Save Recorded waveforms to the VG hard drive, Press “FILE”.
90 Recording waveformsAfter pressing “SAVE” the above message will be displayed whilst saving.Previously “saved” recordings can be found by pressing “OPEN”.
91 Zooming recorded waveforms Time base zoomVoltage zoomPreviously recorded waveforms can be “Zoomed” in or out for better viewingby pressing “ZOOM”.
92 Recording waveformsWaveforms can be zoomed, both in voltage and time, by touching the arrowsabove.
93 Recording waveformsNote here that the time base has been divided by 2, making the time base5 ms / div instead of 10 ms as it was when recorded. It may also be multiplied
94 Recording waveformsNote here that the voltage scale has been multiplied by 2, making theVoltage 1v / div instead of 2v as it was when recorded.
95 Trigger SettingsBefore discussing the various possible trigger settings available onthe Carman Scan VG, it should be noted that in most cases the VGuser doesn’t have to make any changes at all to trigger settings.This Powerful, user friendly Oscilloscope automatically sets all thebasic scope settings ready for testing by any user, whether highlyexperienced or a total novice.
96 Setting a Trigger point on an Oscilloscope, gives the scope a reference point at which to start the pattern display on the screen.The trigger point can be set at any position, and on any channelof the scope.An example of using a trigger would be:When displaying Secondary Ignition patterns, the “trigger” pickup isattached to # 1 HT lead.This means that the first cylinder to be displayed on the screen willbe # 1 (the trigger cylinder) followed by the remaining cylinders inthe firing order.If we removed the trigger pickup, the patterns may still be displayed,however, there would be no way of identifying the correct cylinders onthe screen as the scope would have no reference point.
97 When using a Lab scope, setting a trigger point will keep the pattern steady on the screen.If measuring signals on more than one channel at a time, thetrigger can be set on any channel.Triggered signals on one channel can be referenced againstsignals on other channels for exact timing etc.E.G.1 Using a Trigger pickup on # 1 HT lead, you can referenceexactly when # 1 spark plug or coil is being fired in relation to theCrankshaft Position Sensor (being measured on another channel).E.G.2 When testing the timing of the Camshaft Position Sensor tothe Crankshaft Position Sensor, triggering the two patterns togetherwill allow you to check the exact position of the sensors in relationto each other, without physically removing any parts.
98 Checking timing of CMP to CKP Sensors Crankshaft (CKP) and Camshaft (CMP) Sensors.Checking correct timing of CMP Sensor
99 Trigger Settings (Note: a trigger gives the scope a reference point, allowing the pattern to be repeated over and over again at the same position on the screen)Trigger on channel 1Making changes to the trigger settings can be done by either touching theappropriate section on the screen or by touching “TRIGGER”
100 Trigger Settings Trigger on channel 1 To change trigger settings select one of the above.
101 Trigger Settings: After touching “TRIGGER” the following selections can be made.Trigger now on channel 2Changing the Trigger channel - Touch “CHANNEL” or touch the screen here.
102 Trigger Settings: Moving the Trigger Point. Drag this towherever you wantTo move the trigger point to a new position, simply touch the screen in the upperleft section and drag the trigger point to a new position on the scope.
103 Trigger Settings: Changing the Trigger Type Triggering ona rising signalOscilloscope triggered on a “Rising” signal. To make the oscilloscope trigger ona falling signal, touch “TYPE” or touch the screen here.
104 Trigger Settings: Changing the Trigger Type Triggering ona falling signalOscilloscope now triggered on a falling signal.
106 The “mode” used to trigger the scope can be changed to suit the user or the test being performed.Trigger Modes available include:1. “Auto” Mode (Default mode)In this mode the VG automatically displays the pattern, regardless of theTrigger level selected.2. “Normal” ModeIn this mode the pattern will not be displayed until the “preset” trigger voltagehas been reached.If selected whilst patterns are currently being displayed, the patterns will befrozen on the screen until the correct trigger level has been set.3. “Single” Mode (Snap-shot mode)In this mode the VG automatically freezes the patterns on the screen as soonas the correct trigger voltage has been reached.
107 Trigger Settings: Changing the Trigger Mode. To change the trigger mode from‘Auto’ to ‘Normal’, touch “MODE” or touch the screen here.
108 Trigger Settings: Changing the Trigger Mode. Trigger mode changed from ‘Auto’ to ‘Normal’.Touch again to change from ‘Normal’ mode to ‘Single’ mode
109 Trigger Settings: Changing the Trigger Mode. Trigger mode changed from ‘Normal’ to ‘Single’.
110 Trigger Settings: Changing the Trigger Mode. When in ‘Single’ mode, the scope will capture a single screen shot only.To display a new screen shot touch “Run/Stop”
111 Testing Injector Patterns To test an injector pattern, connect one of the lab scope leads to theNegative terminal of the Injector to be tested.
112 After selecting Inject… and the Channel # Testing Injector PatternsPress “SAVE” when completedAfter selecting Inject… and the Channel #press “SAVE” to progress to Lab Scope screen.
113 Testing Injector Patterns Injector Off Spike ( Usually 70 – 100v).Battery volts.Battery volts.Zero volts.Injection Duration.Typical Injector Pattern at Idle. To check the exact injector duration use theCursors.
114 Testing Injector Patterns Curser.# 1To use the Cursers touch “CURSER” once to bring up the first curser. Drag the first curser to the start of injection. Touch “CURSER” again for the second Curser. Drag the second cursor to the end of injection.
115 Testing Injector Patterns Second Curser.The Injection duration (3.36 m/s is displayed as “SET TIME” at the bottom of the screen. The voltage difference is also displayed (13.25v)
116 Testing MAP and Throttle Position Sensors Engine drivability problems can often be caused by incorrectoperation of MAP or Throttle Position Sensors.The Oscilloscope is an excellent way of testing both of thesesensors for correct operation.
117 After selecting the second channel press “SAVE” to Testing Throttle Position Sensor and Map Sensor SignalsPress “SAVE” when completedAfter selecting the second channel press “SAVE” toprogress to Lab Scope screen.
118 Testing Throttle Position Sensor and Map Sensor Signals Full ThrottleThrottle PositionSensor SignalMap Sensor SignalMaximum Vacuum during decelerationCheck for smooth rise and fall in signals as accelerator is snapped open and closed.
119 Testing Throttle Position Sensor and Map Sensor Signals Approx 4.3vThrottle PositionSensor SignalApprox 0.35vMap Sensor SignalApprox 4.0vApprox 1.3vApprox 0.7vTypical Readings.
120 Testing Idle Control Motors OpeningsideClosingside
121 Testing Idle Control Motors With 3 wire type Idle Control Motors, the centre terminal isusually supplied with battery volts, while the two outside wiresare switched to ground by the ECM using a variable duty cycleat a constant frequency.One side is the opening side and the other is the closing side.The duty cycle on one side is inversely proportional to the dutycycle on the other side.E.g. If the duty cycle on the opening side is 70%, the duty cycle onthe closing side will be 30% and visa versa.
122 Testing ISC Duty Cycle Motor Type OffOpening Side = Approx 35%OnClosing Side = Approx 65%OffOnTesting IAC Motor at hot idle with no load.
123 Testing ISC Duty Cycle Motor Type Opening Side = Approx 42%OffOnOffClosing Side = Approx 58%OnTesting IAC Motor at hot idle with Air Conditioning on.
124 Testing Oxygen Sensors There are two main types of oxygen sensors used on vehiclestoday.1. Zirconium (voltage generator type)2. Titanium (variable resistor type)As the Oxygen sensor is such an important part of the “ClosedLoop” feedback system, it is extremely important that you havea thorough understanding of the correct testing procedures.A faulty Oxygen Sensor not only has a detrimental affect onvehicle emissions and fuel economy, it can also cause dramaticdrivability problems.The following is a description of the testing procedure for aZirconium Oxygen Sensor.
126 Selecting Oxygen Sensor Test Press “SAVE” when completedAfter selecting the type of oxygen sensor and the channelPress “SAVE” to progress to Lab Scope screen.
127 Good Oxygen Sensor Pattern at 2500 RPM Rich1 Second5 CrossoversLeanThe “crossover” is the point where the 02 sensor signal crosses the midway(approx 500mv) point in the signal. The oxygen sensor’s speed is measuredas the number of “Crossovers per Second”
128 Good Oxygen Sensor Pattern at Idle 1 Second2 CrossoversNote the slower speed of the 02 Sensor at idle.
129 Bad Oxygen Sensor Pattern at 2500 RPM 02 sensor voltage staying high (approx 800mv)To test if the 02 sensor is causing the fault, disconnect aninjector and check for a sharp drop in the signal.If the signal drops sharply the 02 sensor is OK and the highsignal voltage is caused by an over rich air fuel ratio.This may be caused by an over-rich air fuel mixture or a faulty(possibly contaminated) 02 sensor.
130 Bad Oxygen Sensor Pattern at 2500 RPM Sharp drop in 02 sensor voltage as injector is disconnectedThis indicates that the high voltage is caused by an over richair fuel ratio, not a faulty 02 sensor
131 Bad Oxygen Sensor Pattern at 2500 RPM To test if the 02 sensor is causing the fault, snap the throttlerapidly a few times or feed some LPG into the intake. If the02 sensor voltage now increases the 02 sensor is OK and thelow signal voltage is caused by a lean air fuel ratio.02 sensor voltage staying low (0v)This may be caused by a lean air fuel mixture, a faulty 02 sensoror grounded wiring.
132 Bad Oxygen Sensor Pattern at 2500 RPM Sharp increase in 02 sensor voltage as throttle is snappedopen a number of times.This indicates that the low voltage is caused by a lean air fuelratio, not a faulty 02 sensor or grounded wiring.
133 Current RampingThere’s no doubt about the value of a current probe for quickaccurate diagnosis.More and more technicians are now starting to realise the valueand are using a low current probe to test things like:Fuel Pump operation/wearIgnition coil operation/available currentCoil on plug and DIS operationInjector operation/available current
134 Testing Fuel Pump Waveforms (Using “Optional” Low Current probe).To test a fuel pump waveform, connect the low current probearound a single wire going to the fuel pump.The electrical condition of a fuel pump can be assessed by viewingthe current waveform for irregularities.Fuel Pump wear can be determined before complete failure occurs.
136 Testing Fuel Pump condition using VG Low current probe connected aroundfuel pump power supply wiring.Normal waveform for good Fuel Pump.
137 Testing DLI Ignition System using Low Current Probe Current Probe around coil power supply wire#1 Trigger Pickup Signal# 1 & 4 SparkPlugs firing hereDwellstartshere# 1/4 Coil# 3/6 Coil# 5/2 Coil#1/4 Crank Angle Sensor Signal from 3 x sensorNormal waveforms.
138 AC CouplingEvery signal we have tested up to this point has been with theOscilloscope set to “DC” coupling.DC Coupling is the Default screen and is the best way to test mostSensors and Actuators etc.AC Coupling can be very valuable however for testing for “noise”on power supplies, checking Alternator diodes etc. or for testingKnock Sensor signals.Only Channel 1 can be AC Coupled
139 Channel 1 connected to vehicle battery with DC Coupling selected To select AC Coupling touch “AC”.Approx 14 volts0 voltsNote: Pattern is DC Coupled at this timeNote: Only Channel 1 can be AC Coupled.
140 Channel 1 connected to vehicle battery with AC Coupling selected Pattern is now AC Coupled.Approx 14 volts AC CoupledNote: To check for any fluctuations in battery voltage change voltage scale toeither 50m/v or 100m/v per div.
141 Channel 1 connected to vehicle battery with AC Coupling selected Voltage scale set to 100mv/DivApprox 14 volts AC CoupledNote: To check condition of Diodes, load Alternator by operating accessories.Maximum variation should be approximately 300m/v
142 Analysing by Trouble Type Another very Powerful feature of the Carman VG is a featurecalled “Analyse by Trouble Type”.With this feature, you can select from a list of possible faults orsymptoms and the VG will automatically select the componentsto be tested for analysing the fault.Each component will be allocated a channel for testing and theOscilloscope channels will be set up with appropriate voltageand time base settings.
143 Touch the“Analyse by Trouble Type” Icon. Analysing by Trouble TypeTouch the“Analyse by Trouble Type” Icon.
144 Analysing by Trouble Type Vehicle FaultPress “SAVE” when completedAfter selecting the type of fault, the components requiring testing will be allocated their channels. Next select “SAVE” to progress to the Oscilloscope.
145 Analysing by Trouble Type Next select the type of sensors on the vehicle (highlighted in bold) and touch “OK” to progress to the Oscilloscope.
146 Analysing by Trouble Type Oscilloscope channels are now set ready for testing of components.
147 In ConclusionThe knowledge gained by attending this course can only be ofbenefit if put into practice as soon as possible.Specialists are not created overnight.They are created by PRACTICE and the willing to learn.Diagnostics is not magic, it perfected by applying BASICS.A knowledge of how a system or component operates is one of themost valuable tools when trying to diagnose a problem.Study the operation of various components and you will find thatit won’t matter what type of vehicle you are working on. They alloperate in a very similar manner.
148 Nextechand Carman Scan VGYour Partners for the Road Ahead!
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