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IMSA Traffic Signal Technician Level II Exam V1 |
(Latest 2025 / 2026 Update) Questions and Verified
Answers | Grade A | 100% Correct
Question:
In a TS2 cabinet, how many times can the MMU experience a "Port 1 Fail" in a 24 hour period before the fault is latched?
Answer:
Question:
On a 2070 MMU monitor unit, how does the field tech program allowable phases?
Answer:
Remove diode on program card for allowable phases
Question:
On an MMU, is it possible to tape the reset button to prevent the traffic signal from going into flash?
Answer:
Yes, it by-passes the conflict feature and will not flash
Question:
On a NEMA CMU program card, how does the signal tech program allowable phases?
Answer:
Install copper jumpers and soldering them on the program card
Question:
According to best maintenance practices, how often should CMU/MMU be tested?
Answer:
Annually
Question:
The MMU indicates a RED-FAIL fault on phase 6. Why?
Answer:
The load switch/switch pack produces no outputs.
Question:
The purpose of the controller CVM (Controller Voltage Monitor) output is to allow the CMU/MMU to
Answer:
monitor the Controller health
Question:
When a Technician is recertifying the CMU/MMU at an intersection, what should the technician do to have the intersection exit flash?
Answer:
Question:
A NEMA CMU/MMU uses a program card to tell the monitor which phases are permitted to run together. Which answer is CORRECT?
Answer:
NEMA monitors have wire jumpers missing in all positions, the tech solders the ones in that allow phases to run together.
Question:
When the controller timings DO NOT match the timing sheet, who should be contacted for correct times?
Answer:
Traffic Engineer
Question:
An older TS1 cabinet experiences a flash condition but the signal heads are also showing active green, yellow, and red indications. What is the MOST COMMON issue?
Answer:
The mercury contactor is stuck in the normal position.
Question:
In a Dual-Ring, 8-phase traffic signal controller, how many phases can run in each ring at the same time?
Answer:
Question:
Observations indicate that vehicles are being detected in one lane and that this is shown on the detection interface unit. However, the controller does not show any detection for that phase. This could be caused by
Answer:
Improper detection phase assignment programming in the controller
Question:
As soon as vehicles leave the detection zone of an approach that has met its minimum green time, a signal immediately goes to yellow from the green display. This could be a result of
Answer:
no extension time programmed.
Question:
What is one reason the phase interval may change even though there is still vehicle demand?
Answer:
maximum green time has been met
Question:
A signal tech is reviewing the controller logs and continually sees a cycle fault error. What does that mean?
Answer:
Beginning of green
Question:
Why is it important for a Signal Tech to verify that the phase concurrency is the same in the controller as it is in the MMU or ATC CMU?
Answer:
The MMU/CMU will keep the cabinet in flash until MMU mirrors what is programmed in the controller
Question:
NEMA Standard TS2-2003 requires all but which of these detector faults to be reported to the controller?
Answer:
Erratic counts
Question:
Observations indicate that a phase is extending to maximum green on every cycle despite no vehicles being present in the detection zone. This could be caused by
Answer:
a damaged loop detector for that phase
Question:
A Tech is troubleshooting a cabinet where the controller is reporting a cycle fail. What does that
mean?
Answer:
There is more time in the sum of the splits than the time programmed for the first cycle.
Question:
An intersection goes into flash every morning at exactly the same time. Which of the following is the LEAST IMPORTANT piece of data that can be retrieved from the cabinet?
Answer:
Controller Voltage
Question:
If a Signal Tech is required to change a timing parameter in the controller, it is MOST IMPORTANT to do which of the following?
Answer:
Alert their supervisor of the changes made
Question:
A signal tech sees that the detection is working properly at the detection device, and is connected to the controller but the controller does not get the input. What could be one of the issues preventing the detection from getting to the controller?
Answer:
The detector is not mapped in the controller correctly.
Question:
Answer:
The previous pedestrian clearance time is recorded in the pedestrian head and used for the next cycle.
Question:
What is the MINIMUM pedestrian clearance time for a crosswalk that is 80 feet (24 meters)?
Answer:
23 seconds
Question:
When checking the pedestrian timing in the controller, what is the proper amount of time that should be given to a pedestrian signal?
Answer:
The clearance time is equal to the width of the intersection divided by 3.5ft/second
Question:
The proper timing for a pedestrian crossing clearance phase is based on which of the following equations?
Answer:
Length of intersection divided by 3.5 f/s (1m/s)
Question:
What is the BEST way to observe proper pedestrian push button activation?
Answer:
Walk the intersection and push each button and observe the response
Question:
According to the NEC(National Electrical Code), GREEN wires in the traffic signal cabinet are only to be used for
Answer:
earth ground within the signal cabinet
Question:
After connecting the phase (2) NB through movement's loops to the vehicle detection board in the traffic signal, what should be verified?
Answer:
That the NB through detection is placing calls on Phase (2) in the controller.
Question:
Which observations for failed loop detection will indicate a field problem?
Answer:
A failed continuity test
Question:
What equipment is NOT used in troubleshooting a video detection system?
Answer:
Answer:
Increases the inductance
Question:
Which detection systems typically cannot be used for pedestrian detection?
Answer:
Loops
Question:
What is the BEST way to determine if a loop wire's insulation has failed?
Answer:
Visual Inspection
Question:
When installing a ground rod it MUST BE installed so that the Technician can obtain an ohm reading of
Answer:
25 ohm or less.
Question:
Logic ground should be
Answer:
Isolated from cabinet.
Question:
What is one of the QUICKEST ways to determine if a piece of electrical equipment has been burnt by a short or high voltage?
Answer:
there will be an odor that can be detected
Question:
What is a MAJOR reason for an AC line filter being installed in a cabinet?
Answer:
To limit damaging effects of transient noise and other interference
Question:
For the Emergency Vehicle Pre-Emption system, what is the BEST way for the Tech to test the operation of the system?
Answer:
Drive the corridor with a vehicle equipped with an EVP transmitter.
Question:
What is the importance of track clearance time in a railroad preemption?
Answer:
It provides the time for vehicles to exit the track area prior to the gates being lowered.
Question:
Question:
Which of the following documents should a technician check when performing controller troubleshooting?
Answer:
Maintenance logs/intersection drawings/timing charts
Question:
What is the standard used to define how traffic signal controllers and networks communicate?
Answer:
National Transportation Communications for Intelligent Transportation systems (ITS) protocol (NTCIP).
Question:
The traffic management center notifies a field tech that the communications to maple st. And 1st street cuts in and out. The tech arrives at the intersection finding the modem is overheating and indicator lights are blank. After about twenty minutes of checking cables, the tech notices the modem is active again and cool to the touch. The TMC confirms communications are restored. The tech Checks the log book and finds this problem is a recuring issue. what should the tech do?
Answer:
Replace the modem
Question:
A managed network switch is being used in the cabinet. What is needed in the IP programming of the controller to get through the switch and to the TOC?
Answer:
Gateway
Question:
The pedestrian assembly (pedestrian 6) on the SW corner was damaged in a traffic accident and the tech cannot repair until the following day. What should the Tech do until they return to replace the pedestrian assembly?
Answer:
Make wiring safe. Bag opposite signal display pedestrian phase (6). Document in cabinet log book and work order system. Notify supervisor that they need a pedestrian display assembly and to schedule the installation.
Question:
After doing any repairs at a traffic signal which of the following is the MOST IMPORTANT to do before leaving the intersection?
Answer:
Observe signal is operating per plans.
Question:
Which of the following could cause signals at an intersection to repeatedly go into flash?
Answer:
The MMU shows conflict on phases 2, 6, and 4 during the red interval on 2 and 6. The phase 4 field terminal is blackened and the terminal screw is loose
Question:
A traffic signal head for phase 8 east bound amber is out; the load switch is blown. The Tech checks field terminals in the cabinet with a multimeter and verifies the wire is shorted. Which of the following options describes the MOST LIKELY cause of the shorted wire?
Answer:
check the line service to make sure there is main power.
Question:
The technician arrives at an intersection that is dark. What type of meter does the technician use the check voltage?
Answer:
Multimeter
Question:
A technician received a call that a signal head was knocked down. The technician arrives on scene, repairs the problem, observes the intersection is functioning properly and completes his job duties. What is the technician's LAST task before leaving the intersection?
Answer:
Document all repairs and the incident in the maintenance logs.
Question:
A technician observes two different colored signals displayed at the same time in one direction. The Tech knows the problem is LEAST LIKELY related to the
Answer:
incoming power
Question:
A technician arrives at the intersection and the light is on flash. What should the technician do?
Answer:
Check the conflict monitor display and then reset it.
Question:
The MOST IMPORTANT thing to do when completing work is to
Answer:
document all changes in the maintenance logs.
Question:
Faulty components should be
Answer:
labelled and marked for repair or disposal.
Question:
What is required where wires enter the traffic fixtures and/or poles to eliminate wire chaffing?
Answer:
Grommets
Question:
All wiring not being used should be
Answer:
attached to ground bar
