Ch.2
When does a splice occur? Or occur for?
Common power or common ground
Can you splice a signal wire ?
No
The time the points remained closed is represented in this section of the pattern.
dwell section
This section ends when the next spark is fired.
dwell section
A short horizontal line in this section indicates spark duration.
firing section
simplified version of removal steps of a distributor is?
1. locate secondary ignition wires 2. remove secondary ignition wires. 3. remove distributor cap. 4. mark rotor position and remove rotor. 5. disconnect vacuum hoses and electrical connections 6. remove distributor
Technician A says that spark plug wires have to match the distributor cap terminals to ensure correct firing order when the distributor is installed. Technician B says that during distributor installation, the oil pump drive needs to be turned when it is not engaged properly. Which technician is correct?
B
The best method for removing spark plug wires is to pull the wire rather than the boot. T/F?
F
The first step to remove the distributor is to remove the rotor. T/F?
F
True or false your power wire always has to be connected to a fuse
False
What does 2 wires on a sensor mean on a wiring schematic mean?
It means that it generates its own voltage and is considered an active wire
Two wires on a sensor means?
It's an active sensor?
Uses a plunger to open a closed switch.
Push Button switch
How could you find your ground wire when testing pins with your multimeter?
Set your multimeter up to ohms, ground a lead and poke the connector pins until your meter beeps
Mark the position of the rotor before removing it. T/F?
T
For a crankshaft sensor on a wiring schematic you might have two wires, one with a plus and one with a minus. Which one is your signal wire? And which one is your signal return/ground wire?
The one with the plus is signal, the minus is the signal return/ground
It reacts to the engine's environment.
Thermostatic switch
Made up of two metals forming a bimetal strip, and it is normally closed.
Timing switch
Power is typically where on a wiring schematic ?
Top to bottom
Would a switch following a wire from back from a sensor be a good indicator of your control wire?
Yes
the ________________ ___________ reduces current flow from the battery to the primary coil.
ballast resistor
Two technicians are discussing wire harnesses. Technician A says retainers and clips provide more protection to the wiring harness. Technician B says grommets help route, protect, and secure wires that pass through the body or frame of the vehicle. Who is correct?
both
On a distributor what is the part that acts as a movable switching device and opens and closes the circuit?
breaker points
Ammeter inductive pickups use the Hall effect principle to measure what?
current flow
Pickup coil camshaft sensors are mounted inside the __________.
distributor
The _________________ uses either a mechanical or electrical triggering device to control current flow through the ignition coil
distributor
What type of ignition system requires less maintenance and is more efficient. this type of system includes a crankshaft position sensor, camshaft position sensor, engine control module, ignition coil, and ignition control module. The electronic modules directly control the ignition coil or coils.
distributorless ignition (electronic ) system
Technician A says that all Hall-effect sensors use an external magnet. Technician B says that all Hall-effect sensors are two-wire sensors. Which technician is correct?
neither
On a distributor what part has a slotted disc that allows or interrupts current flow and uses a beam from an LED?
optical sensor
The __________ has been used with various fuel and ignition systems.
pickup coil crankshaft sensor
The __________ is common in many transmissions.
pickup coil vehicle speed sensor
Crankshaft position sensors use a ________ ___________ or _____________ ____________ mounted to the crankshaft to toggle the Hall effect voltage and produce the signal
steel interrupter or reluctor ring
The __________ provides input to the EBCM.
wheel speed sensor
Why would high voltage be needed to run through the ignition coil ?
to jump the air gap across a spark plug and begin the combustion process in the engine.
what are the steps in operation of a optical sensor functioning ?
1. LED light shines. 2. a disc interrupts the light beam. 3. photocells detect the light beam 4. a photo transistor signals the switch to turn on and off. 5. the electronic control module determines the speed and direction of rotation of a component.
What are the steps in removing the distributor for service?
1. Locate, inspect and mark the secondary ignition wires connected around the perimeter of the distributor cap. The secondary wires are arranged on the distributor cap in a specific engine firing order. If you place the secondary wires out of order during installation, the engine will misfire. 2. Slightly twist and wiggle the spark plug wire boot until you can remove the secondary ignition wires or spark plug wires. In order to avoid pulling out the terminal, do not pull on the spark plug wire. 3. The distributor cap attaches to the housing with screws or quick release clamps. remove the retaining screws or clamps and lift the distributor cap off the distributor housing. It is important to inspect the distributor cap for cracks or carbon tracking. 4. Next mark the position of the rotor on the distributor housing or a location near the distributor, and remove the rotor. 5. Disconnect the vacuum hoses and electrical connections from the distributor. 6. Place a mark on the distributor housing and on the engine block to allow for proper realignment when you reinstall the distributor. Remove the distributor hold down bolt and bracket connected to the engine. Slowly lift up on the distributor. The distributor shaft spins as the distributor housing comes up due to the shape of the drive gear.
What are the steps in installation of the distributor ?
1. Place the distributor rotor on the distributor shaft. 2. orient the distributor into the right position using the marks you made on the housing when you removed it. using the rotor, slightly rotate the distributor shaft to align the distributor shaft gear with the camshaft gear. As you install the distributor, the rotor will rotate as it meshes with the cam drive gear. When the distributor is seated, the rotor should align with the mark you made during removal. 3. Some engines use the distributor shaft to drive the oil pump. if the distributor will not mount flush against the block, the distributor shaft did not properly connect with the oil pump drive. Remove the distributor and use a specialized tool, such as an oil pump priming tool to turn the oil pump drive approximately one third turn. Then, reinstall the distributor. Repeat until the oil pump shaft properly engages the distributor and allows it to mount flush or tightly to the engine. 4. Rotate the distributor housing until the mark on the blocks aligns with the mark on the housing and ensure that the rotor aligns with the mark you made on the distributor housing during removal. The distributor housing alignment may be slightly off after the distributor is seated, but this can be adjusted when setting the base timing. 5. Install the distributor hold down and bolt to the engine. 6. connect the primary wiring and any necessary vacuum lines to the distributor. 7. install the distributor cap and the secondary ignition wires. Proper installation of secondary wiring is critical. The proper cylinder spark plug wires must be matched to the proper terminals on the distributor cap to ensure proper firing order.
what are the steps of an ignition coil operation in the proper order?
1. The control device closes and current flows to the coil's primary windings. 2. Current flows through the primary windings, creating an electromagnetic field. 3. Current continues to flow through the primary coil winding for a short time, saturating the magnetic field. 4. The control device opens the primary coil circuit, stopping the current flow. 5. The magnetic field quickly collapses and magnetic force moves toward secondary windings. 6. The primary coil's magnetic field collapses, inducing high voltage in the secondary coil.
What are the steps in the hall effect sensor working?
1. The shutter wheel rotates and the blade moves between the magnet and the gallium arsenate crystal. 2. A weak analog signal goes low. 3. The signal is sent to the amplifier, where it is amplified and inverted. 4. The high signal is sent to the Schmitt trigger, where it is changed to a digital signal. 5. The digital signal is sent to the switching transistor. 6. The signal leaves the Hall-effect sensor and is carried through the vehicle's wiring to the PCM.
explain the steps in how a breaker point ignition system operates
1. you turn the ignition key to the start position. 2. The starter relay and starter motor receive power and turn the engine over. 3. The ignition coil primary windings receive power from the ignition switch. 4. As the engine turns over, the distributor shaft rotates, driven by the engines camshaft or auxiliary shaft. 5. This causes the breaker points to open and close which starts and stops current flow to the primary side of the ignition coil. 6. As the breaker points open and close, the magnetic field around the primary wires builds and collapses. This collapsing field creates the high voltage in the secondary side of the ignition coil.
Why would you want to monitor the signal wire when hooking your oscilloscope?
Because that's the wire that is feeding information to your PCM
Why do you need to snap the throttle when measuring MAF
Because when you floor the throttle you let the maximum amount of air (real quick) through
A plunger opens a circuit when depressed, and it is used to activate dome lights.
Contact switch
Shows a vertical line that indicates the voltage needed to fire a spark plug.
Firing section
F18/10A. What does this mean?
Fuse name is F18 and it's a 10 amp fuse
What should you remember for throttle position sensor?
It's a key on engine off test. You're going to cycle the throttle when you measure it which means just floor it real quick
Used to close metal connections and can be located in engine compartments.
Mercury switch
It has a single set of normally closed contacts and is used to control a sunroof.
Micro switch
When looking at a wire on a sensor are you going to get a signal or pattern on your ground wire?
No
If you have a sensor and you're looking at the pins for the sensor, representing say three wires in this case, which means your going to have DC current running through one at all time. How could you use your multimeter to find which wire is your constant power wire?
Set your multimeter up to DC voltage, ground your ground lead and poke your red lead to each connector pin until you find the one that has voltage
Why would you use your trigger on the oscilloscope when testing fuel injectors?
So you can catch the voltage spike pattern of the fuel injector injecting fuel.
A dot on a wiring schematic represents what?
Splice
Some engines use the distributor shaft to drive the oil pump. T/F?
T
When you're looking at the different wires coming off a sensor, like say for instance that you're trying to figure out which wire is the signal wire for the sensor, what do you need to keep in mind ?
That sensors have different components and because of that you have wires coming off the same "sensor" on the diagram that aren't necessarily representing the sensor portion of the sensor.
When you are asked what the voltage by division is For the oscilloscope how you determine that?
The left hand side you can see what section of the boxes represent (like a graph). If it's going up in twos; ie: 2,4,6,8. It's 2.
Classified as a multiple pole, multiple throw with a mechanical handle.
Toggle switch
True or false you can have a power wire or aground wire coming off the PCM
True
Would a wire following a sensor back to the PCM be a good indicator of your control wire?
Yes
What's a good indicator that a wire is a power wire?
You follow it back to a fuse
If you're testing a speed sensor, what do you need to keep in mind?
You need to have the car in drive to test it appropriately. If it's an idle you're not testing speed
For the oscilloscope what do you need to do to find your hertz reading or frequency reading? Say for your camshaft sensor?
You need to pause your pattern, turn in your cursors and reference them to each other properly and you should get your hertz reading on the bottom right hand corner.
What do you need to do to get an accurate reading on the oscilloscope when measuring mass air flow?
You need to take a snapshot of you flooring it really quick (snapping the throttle). Then put your cursors on the beginning or where the line was at idle and the peak of the throttle snap. You'll then have your delta reading (difference between two markers)
For the oscilloscope when setting up your cursors what should you keep in mind?
You should set them up one at the beginning of one cycle to the beginning of the next or just make sure you're putting them in the same place in regard to each other
Why would you have a difference in frequency between your crankshaft sensor and your camshaft sensor?
Your crankshaft sensor spins or cranks twice as fast than your camshaft so your crankshaft will have a higher frequency
Technician A says that some pickup coils are adjustable. Technician B says that there should be contact between the pickup coil and the rotating trigger wheel. Which technician is correct?
a
Technician A says that the DMM could be set to volts or ohms to test for circuit faults. Technician B says only a DMM can be used to detect circuit faults. Which technician is correct?
a
what part on the distributor has a metal tab on a trigger wheel that interrupts the magnetic field ?
hall-effect Pick up sensor
the _____________ ______________ allows current to flow to the components of the ignition system.
ignition switch
The _____________ _______________ connects spark plugs to the distributor cap
ignition wires
The oscilloscope pattern displays three or more oscillations in a normal ignition system.
intermediate section
The pattern in this section represents remaining energy that flows through the secondary windings of the ignition coil.
intermediate section
On a distributor what parts contains a reluctor that interrupts the magnetic field. this disruption sends electrical signals to the ignition module?
magnetic pickup coil
what creates and delivers the spark?
spark plugs and ignition wires
