A6 Electrical &
Electronic Systems
With the ignition off and the network asleep, resistance between CAN High and CAN Low at the data link connector measures 120 ohms. Which of these could be the cause?
A remote keyless entry fob operates only within a few feet. Technician A says a weak fob battery could be the cause. Technician B says a replacement fob must be programmed to the vehicle. Who is right?
Both low beams work but neither high beam illuminates. The high beam indicator lights normally. Which of these could be the cause?
A clamping diode installed across a relay coil is used to:
A three-year-old battery reads 12.6 volts open circuit but drops to 8.9 volts during cranking. What is the MOST likely cause?
Before replacing a driver door module for an inoperative power mirror, the technician should first:
Which of these is the LEAST likely cause of an intermittent electrical fault that appears only over rough roads?
Technician A says a charging system voltage output test should be run with the accessories switched off. Technician B says a generator with an open field winding still produces full output at high speed. Who is right?
All power door locks operate from the driver's switch, but none respond to the key fob. The fob battery is good. Which of these could be the cause?
Both headlights are dim with the engine running. The readings below were taken with the lights on. Which of these could be the cause?
| Test point | Reading | Specification |
|---|---|---|
| Battery positive to headlight feed | 0.3 V | 0.5 V maximum |
| Headlight ground to battery negative | 0.9 V | 0.2 V maximum |
| System voltage, engine running | 14.1 V | 13.5–14.7 V |
| Headlight current draw | 3.1 A | 4.0 A maximum |
The clockspring in a steering column is used to:
Any of these could cause a no-crank condition with no solenoid click EXCEPT:
A scan tool displays a sensor signal of 5.0 volts on a circuit that should read 0.5 volt. What is the MOST likely cause?
Technician A says ice or mud on a park assist sensor face can set false alerts. Technician B says park assist sensors are tested by measuring resistance across their terminals. Who is right?
Before aiming the headlights on a vehicle, the technician should:
A 10-amp fuse supplying the interior lamps blows whenever the rear hatch is opened. Which of these could be the cause?
Which of these is the LEAST likely cause of an infotainment display that goes blank intermittently?
The battery case is hot and the electrolyte level is low. Charging voltage measures 16.2 volts at 2000 rpm against a specification of 13.5 to 14.7 volts. Which of these could be the cause?
Technician A says corrosion under a battery clamp can cause slow cranking even when the clamp feels tight. Technician B says the drop across that connection should be measured while cranking. Who is right?
A power seat moves forward and back but will not recline. What is the MOST likely cause?
An electronic combination flasher in a turn signal system is used to:
To measure current draw in a circuit with a digital multimeter, the technician should:
The engine starts and immediately stalls, and the security indicator flashes afterward. Which of these could be the cause?
Which of these is the LEAST likely cause of a battery that is discharged each morning after the vehicle sits?
Technician A says a charging circuit voltage drop test is performed with the engine off. Technician B says a computer-controlled charging system may vary target voltage with battery temperature. Who is right?
Reading Your Results: A6 Electrical and Electronic Systems, Test 2
This test comes at the same content areas from the network and the body accessories rather than the starting and charging systems. More of these questions are decided by what still works than by what does not, so the recurring skill here is using the working half of a circuit to eliminate everything it proves.
If you missed the questions where something still worked
Several questions on this test hand you a fault along with a list of things that are still functioning, and that list is the diagnosis. Both low beams working while neither high beam does means the bulbs, the grounds, and the supply are all fine, so the fault is in what only the high beams use. Door locks working from the driver's switch but not from the fob means the motors, the wiring, and the module output are proven, so the fault is in the receiving side. A power seat that moves fore and aft but will not recline means the module, the ground, and the switch assembly are all working for one function and not the other. Before choosing an answer, write off everything the working function has already proven, because it usually leaves one option standing.
If you missed the questions built on a measurement
Three questions here give you readings, and each is asking whether you know what that number is describing.
If you missed the component function questions
The three component questions here each solve a problem created by the circuit around them. A clamping diode across a relay coil gives the collapsing magnetic field somewhere to go when the coil is switched off, so the resulting voltage spike does not damage the driver or the module switching it. A clockspring is a coiled ribbon conductor that carries circuits into a steering wheel that has to rotate, which is why airbag, horn, and wheel control faults so often trace back to one part. An electronic combination flasher handles both turn signal and hazard operation and does not change rate with a burned-out bulb the way a thermal flasher does, which matters because an LED-equipped vehicle needs a different bulb-out strategy entirely.
If you missed the EXCEPT and LEAST likely questions
Four appear on this test, and the method is the same one that works on the real exam. Identify what the three real causes share before hunting for the odd one out. On the intermittent-over-rough-roads question, three answers all describe a connection that can make and break with movement, and one is a fault that would be constant. On the no-crank with no solenoid click question, three answers all interrupt the control circuit that energizes the solenoid, and one affects the high-current path after the solenoid has already pulled in. Naming the shared trait first is faster and far more reliable than working through four options one at a time.