Exam 12: Multiplexing

Technician A says that a high bus backbone consists of a twisted wire pair wound with bare copper wire and wrapped with a foil shield.Technician B says that the bare copper wire used in a high bus backbone is known as the drain.Who is correct?

Technician A says that the physical distance between the two wires on a twisted wire pair determines their capacitance,with capacitance decreasing as the wires become further apart,accounting for the fact that replacement is usually preferred over repair.Technician B says that the insulation wrap over a twisted wire pair also defines the capacitance which explains why it should never be replaced with ordinary wire.Who is correct?

What color is assigned to the physical power line carrier (PLC)communication between a tractor and trailer?

What type of data connector is associated with the SAE J1587/1708 data bus?

Which of the following messages broadcast to a truck data bus would probably be assigned the highest priority?

What is the resistance of a terminating resistor used on a J1939 data backbone?

What is the usual voltage differential used on the J1939 data backbones to transmit message packets?

Technician A says that if one module networked to a J1939 data bus fails,it should not affect the operation of other modules on the bus.Technician B says that an advantage of using a data bus,is that controllers on the bus can share input signals from key components such as a TPS.Who is correct?

When the LED on a smart switch flashes,what does that tell the operator?

What universal standards are used to ensure that control module interconnectivity on J1939 adheres to both national and international standards?

Which of the controllers is 'in charge' of managing data on a truck J1939 data bus?

How many terminating resistors are required on a J1939 data backbone?

Which of the following DLCs would be required to access the J1939 data bus of most MY 2014 and later trucks?

Technician A says that CAN L (-)and (chassis)ground are of equal voltage potential.Technician B says that modules networked to a J1939 bus are designed to identify the difference between CAN H (+)and CAN L (-)in message packet without reference to chassis ground.Who is correct?

Technician A says that a disadvantage of multiplexing is that it increases the amount of wiring on a vehicle chassis.Technician B says that a Navistar Diamond Plus multiplex dash has just 7 wires as opposed to over 60 wires on earlier Navistar dash.Who is correct?

When power line carrier (PLC)multiplexing is used,what vehicle system is it associated with?

What is the advantage of using serial data transmission on a current truck data bus as compared with a multiple track (parallel)model?

What is the current automotive/ light-duty truck equivalent of the J1939 data bus used on medium/heavy trucks on passenger cars and light duty trucks?

Which source address (SA/MID)code identifies the address of the transmission electronics on a truck data bus?

Technician A says that diagnostic trouble codes (DLCs)are tagged with an FMI.Technician B says that every DLC is tagged with an OC.Who is correct?