Free ASE H6 Transit Bus Electrical/Electronic Systems Test Practice Questions

Sample Practice Questions

Try these 10 sample questions from the ASE H6 Transit Bus Electrical/Electronic Systems Test practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1An operator reports that a bus electrical accessory fails only after several minutes on a rough route. What should the technician do to verify this complaint?

   1. A. Replace the accessory based on its service age.
   2. B. Attempt to reproduce the failure under the reported conditions.
   3. C. Clear stored faults and release the bus without a functional check.
   4. D. Test a spare accessory without operating the installed circuit.

   Answer: B

   Explanation: ASE specifies: "Verify operator complaint, reproduce the condition (including intermittent problems), and/or road test vehicle; determine necessary action." Reproducing the reported operating conditions establishes whether the intermittent symptom occurs. Replacement, code clearing alone, and a spare-component test do not verify operation of the installed circuit under those conditions.

   Reference: ASE Transit Bus Study Guide 2026 — Page 29, task A.1

2. 2A flooded lead-acid starting battery is rated at 800 CCA. Under the Delco Remy load-test procedure calling for one-half of the CCA rating, what test current should be applied?

   1. A. 200 A
   2. B. 800 A
   3. C. 400 A
   4. D. 1600 A

   Answer: C

   Explanation: The procedure specifies: "Apply test load of 1\2 CCA rating at 0˚F in amps." One-half of 800 A is 400 A. The other choices represent one-quarter, the full rating, or twice the rating rather than the specified test current.

   Reference: Delco Remy Diagnostic Procedures Manual for Starters and Alternators — Printed page 12, Battery Test Procedure — Test, step b, one-half CCA load

3. 3A bus dash voltmeter indicates overcharging. Before condemning the charging unit, what comparison is called for in Delco Remy's overcharge diagnosis?

   1. A. Compare the dash reading with direct voltage at the alternator.
   2. B. Compare the dash reading only with engine-off battery OCV.
   3. C. Use the alternator amperage rating to infer actual charging voltage.
   4. D. Use the charge-warning lamp state instead of measuring voltage.

   Answer: A

   Explanation: The chart specifies "CHECK VOLTS AT ALTERNATOR" and includes "CHECK DASH VOLTMETER" when appropriate. A direct charging-voltage measurement distinguishes indicator error from actual overcharge. Engine-off OCV, current rating, and warning-lamp state do not directly measure the operating output voltage.

   Reference: Delco Remy Diagnostic Procedures Manual for Starters and Alternators — Printed page 8, section 2-1, Overcharge Symptoms flowchart

4. 4A bus H4 halogen headlamp works on high beam but not low beam. Why does the working high beam fail to rule out a bulb defect?

   1. A. An H4 uses one filament with electronic PWM selecting both beams.
   2. B. An H4 changes beams by moving a shutter around one filament.
   3. C. An H4 uses a single filament with a separate low-beam ballast.
   4. D. An H4 has separate low-beam and high-beam filaments.

   Answer: D

   Explanation: HELLA describes H4 as a "dual-filament bulb for combined low beam and high beam." One filament can fail while the other still operates. PWM selection, a movable shutter around one filament, and a separate low-beam ballast describe different concepts rather than the H4 dual-filament arrangement.

   Reference: Light Is Knowledge — Technologies, Lighting Systems, Diagnostics — Common Light Sources, H4 entry, printed pages 76–77

5. 5A bus's analogue SingleViu pressure gauge gives consistently incorrect readings at steady pressure after a sender with a different resistance curve is installed. Wiring and supply checks pass. Which correction addresses this calibration mismatch?

   1. A. Configure the sender characteristic to match the installed sensor.
   2. B. Increase needle damping until a steady reading becomes accurate.
   3. C. Raise the warning threshold to rescale the indicated pressure.
   4. D. Keep the original curve because both senders use resistance signals.

   Answer: A

   Explanation: The manual states that gauges can be "reconfigured to other characteristics or pulse values using the ConfigTool." The sender curve maps the measured resistance to pressure and must match the installed sensor. Damping changes response speed, not a settled calibration error. A warning threshold controls alarm activation rather than rescaling the needle. Two resistance senders need not share the same characteristic.

   Reference: SingleViu Operating Manual — Page 13, section 5.1, Needle and signal input; page 32, Sensor characteristics

6. 6A bus accessory briefly loses supply voltage during operation, but a technician cannot watch the meter continuously. Which Fluke 88 V feature can retain the lowest voltage reached during the test?

   1. A. Relative mode to subtract test-lead resistance.
   2. B. HiRes mode to display additional digits.
   3. C. MIN MAX recording to store input extremes.
   4. D. AutoHOLD to retain the first stable reading.

   Answer: C

   Explanation: The manual states: "The MIN MAX mode records minimum and maximum input values." This lets the technician retain a low reading while reproducing the intermittent condition, subject to the selected response time. Relative mode subtracts a reference, HiRes increases resolution, and a stable held reading does not preserve a subsequent minimum.

   Reference: Model 88 V Automotive Multimeter Users Manual — Page 31, MIN MAX Recording Mode

7. 7A battery tester reports a bad battery when connected to its threaded studs. Before accepting the result, which connection correction does Delco Remy specify?

   1. A. Retest on lead pads or the specified terminal adapters.
   2. B. Retighten the tester clamps on the threaded studs only.
   3. C. Increase the test load while retaining stud-only connections.
   4. D. Accept the stud-connected result without a connection check.

   Answer: A

   Explanation: Delco Remy states: "Testing using the studs can create a false bad battery reading." The specified correction is testing on the lead pads or using the correct terminal adapters. More clamp force or test current does not substitute for the required test contact, and accepting the result without correcting that contact risks false replacement.

   Reference: Delco Remy Diagnostic Procedures Manual for Starters and Alternators — Printed pages 11–12, threaded-terminal testing note

8. 8Under the Delco Remy alternator-output diagnostic procedure, battery, wiring and drive checks pass. Output remains zero after the specified residual-magnetism restoration and repeated output test. What action is specified?

   1. A. Continue recharging the tested batteries without repairing the alternator.
   2. B. Replace the alternator after the repeated zero-output result.
   3. C. Increase battery CCA without correcting the zero-output fault.
   4. D. Replace only the dash indicator while leaving the alternator unchanged.

   Answer: B

   Explanation: After the restoration step, Delco Remy directs: "Repeat steps 1 and 2. If output is still zero, replace the alternator." The completed tests justify replacement. Battery charging, a CCA increase, and an indicator replacement do not correct the repeated measured alternator-output failure.

   Reference: Delco Remy Diagnostic Procedures Manual for Starters and Alternators — Printed page 20, section 3-31, Alternator Amperage Output Test, step 4

9. 9A bus uses the Grote LED headlamp type addressed by GLB2020-120. It operates normally from steady headlamp power but flickers on a PWM daytime-running-light feed. What explains the DRL symptom?

   1. A. The pulsed DRL supply can cause these LED headlamps to flicker.
   2. B. The alternator must be defective whenever the DRL reading is below 12 V.
   3. C. The LED source keeps glowing continuously through every supply gap.
   4. D. The headlamps require AC rather than DC to work without flicker.

   Answer: A

   Explanation: Grote states: "DRL or energy saving headlight controls use a PWM signal (a pulse on/off signal) instead of steady DC voltage. This can cause LED lights to flicker." The stated pulsed feed explains the mode-specific symptom. A lower average DRL reading does not establish an alternator fault, and neither continuous filament-like persistence nor an AC supply requirement describes these LEDs.

   Reference: Grote Heated Headlights Q&A — Page 1, Troubleshooting, item 4

10. 10A SingleViu gauge follows a correct changing sensor signal unusually slowly after configuration work. Which parameter specifically controls the needle's response damping?

    1. A. The CAN transmitter source address.
    2. B. The upper warning threshold.
    3. C. The dial illumination percentage.
    4. D. The PT1 needle-damping filter setting.

    Answer: D

    Explanation: Under Needle damping, the manual states: "This value sets the parameters of the PT1 filter for damping the speed of the needle." That setting affects how quickly the displayed needle responds. Source-address selection, warning thresholds, and illumination intensity perform different functions.

    Reference: SingleViu Operating Manual — Page 32, section 8.3.7, Needle damping