Exam 36: Multiplexing

When troubleshooting a J1939 bus, what has occurred if a suspect parameter group (SPG) is assigned to a component??

When you have to work with multiple OEM chassis data bus systems, which type of communication adapter (CA) is recommended??

Technician A says that the secret of effectively repairing a break in the twisted wire pair used in a J1939 data bus is to use plenty of solder in the repair joint to minimize resistance. Technician B says that a damaged Hi bus J1939 twisted wire pair should be replaced, rather than repaired. Who is correct?

What is the usual low bit voltage on a J1939 data transaction?

How many resistors are contained in the ladder bridge of a 2-pole, Freightliner M2 smart switch?

What early multiplexing technology was used to enable trailer ABS electronics to communicate with the tractor?

Which of the following terms best defines the speed limit on a telecommunications channel?

Technician A says that a green 9-pin J1939 DLC must be used to connect to a post-2014 truck powertrain data bus. Technician B says that the black 9-pin J1939 DLC cannot connect to a post-2104 data bus. Who is correct?

Technician A says that a data packet in a typical J1939 transaction consists of 7 fields. Technician B says that each field in a J1939 data packet has identical data volume. Who is correct?

When a J1939 bus shorts to the ground side of the circuit, what is the likely outcome?

When a voltage of value of 12 volts is measured off the CAN high line of a properly functioning J1939 data backbone, what is happening?

What is the usual voltage differential of a J1939 message stop bit?

Which of the following is a major advantage of using an FET as a switch relay over a conventional relay?

Which of the following is used on a data bus backbone to minimize EMI (electromagnetic interference)?

Technician A says that the reason for twisting the wires on a J1939 data backbone is to enable the data bus to act as a giant aerial. Technician B says that J1939 requires the data wire pair to cycle through one full cycle twist per 1 centimeter of length. Who is correct?

Technician A says that the contents of any data bus message packet can be interpreted using a high frequency scopemeter. Technician B says that a scopemeter can be used to identify bus node activity ... or lack of activity. Who is correct?

When an FET output permits excessive current flow on a multiplexed chassis, what circuit protection device opens the circuit?

What is the advantage of using FETs as relays in multiplexed truck chassis?

Which of the following is a correct interpretation of the acronym PLC when it is used in the context of trailer wiring?

Technician A says that OEMs permit some repairs to be made to low bus wiring. Technician B says that when a bus twisted wire pair is protected with foil, you can assume that it is categorized as low bus. Who is correct?