ASE G1 Auto Maintenance and Light Repair flashcards

Symptoms of a failing charging system include an illuminated charging indicator light, low system voltage, and a discharged battery.

• Normal charging voltage is typically 13.5-14.8 volts with the engine running.
• A voltage reading near battery voltage (e.g., 12.2V) with the engine running indicates no charging.
• Common causes include alternator failure, drive belt issues, or wiring problems.

Memory trick: Light on, volts low, belt's gone, no charge flow.

A test to measure the amount of electrical current drawn from the battery by vehicle components when the ignition is off, used to diagnose unexplained battery discharge.

• Normal draw is typically 20-50 mA.
• Excessive draw indicates a faulty component.
• Fuses are pulled to isolate the circuit.

Memory trick: Find the 'leak' draining the battery.

A battery load test assesses a battery's ability to deliver current under a simulated starting condition.

• Healthy batteries should maintain at least 9.6 volts for 15 seconds during a load test.
• Voltage dropping below 9.6V or significantly reduced CCA indicates internal battery issues.
• Load tests are performed on fully charged batteries.

Memory trick: Voltage drops, CCA flops, battery stops.

If a 'CHECK GAUGE' warning light is on, but all individual gauges are functioning normally, the fault typically lies within the instrument cluster's internal diagnostics or programming.

• Indicates a conflict between warning and actual gauge readings.
• Points to instrument cluster itself as the source.
• Requires advanced diagnostic procedures for the cluster.

Memory trick: Gauge Light On, Gauges Right: The Cluster's Own Plight.

When both high beams and the high-beam indicator light are inoperative, the fault typically lies in the control circuit (e.g., headlight switch) rather than the bulbs themselves.

• Indicator light status is crucial.
• Both high beams affected.
• Points to a common control point.

Memory trick: High Beam Out, Indicator Too? Switch is the Clue!

A voltage drop test measures the resistance in a specific part of a circuit by checking the voltage difference across that component or wire while current is flowing.

• Positive side voltage drop (battery to starter B+ terminal) should be 0.2V or less.
• Negative side voltage drop (starter ground to battery ground) should be 0.2V or less.
• Higher readings indicate excessive resistance (corrosion, loose connections, damaged cable).

Memory trick: High drop means resistance's crop.

Parasitic draw is the normal and abnormal current draw from the battery when the ignition is off and the vehicle is 'asleep'.

• Normal draw is typically 20-50 mA (0.02-0.05 amps).
• Excessive draw can drain the battery, especially if the vehicle sits for extended periods.
• Requires an ammeter connected in series with the battery cable.

Memory trick: Fifty mA or less, battery blessed.

Slow cranking with headlight dimming, despite a good battery, indicates high resistance in the starter circuit or a struggling starter motor, leading to excessive current draw and voltage drop.

• Good battery ruled out.
• Headlight dimming points to high current draw.
• Focus on starter circuit components.

Memory trick: Cranking Slow? Check the Flow!

A voltage drop test on the negative side of the starter circuit measures resistance in the ground path between the battery negative post and the engine block. Acceptable drop is typically 0.2V or less during cranking.

• Measures resistance in the ground circuit.
• Connected between battery negative and engine block.
• High reading (e.g., >0.2V) indicates excessive resistance.

Memory trick: Voltage Drop: Power's Path, Check the Math!

When only one power window fails to operate, typically indicating a localized issue with that specific window's motor, switch, or wiring.

• Affects only one window.
• Other windows/accessories function normally.
• Points to motor, local switch, or wiring specific to that window.

Memory trick: One window stuck, not the whole house, so check its own 'engine'!

The measurement of the remaining rubber on a tire's tread, crucial for traction and safety.

• Minimum legal tread depth is 2/32 inch in most regions.
• Tread wear indicators (wear bars) become flush with the tread when worn.
• Adequate tread depth is vital for water displacement and grip.

Memory trick: Tread's Low, Time to Go!

The angle of the wheel relative to the vertical axis when viewed from the front or rear of the vehicle.

• Positive camber: top of the wheel tilts outward
• Negative camber: top of the wheel tilts inward
• Affects tire wear and handling characteristics

Memory trick: Can't Always See The Right Angle.

Headlights that sporadically flicker or cease operation and then resume, often indicating a problem with a shared control component like the headlight switch or a loose connection.

• Affects both headlights (usually).
• Sporadic flickering or complete loss/return.
• Often points to a control component or loose connection.

Memory trick: Flicker, flicker, where's the common link in the light's dance?

A Diagnostic Trouble Code indicating a malfunction in the heater circuit of the upstream (Bank 1, Sensor 1) oxygen sensor, preventing it from reaching operating temperature efficiently.

• Specific to O2 Sensor 1, Bank 1 heater circuit.
• Heater circuit ensures rapid sensor warm-up.
• Affects fuel mixture control and emissions.

Memory trick: P01xx: The 'O' is for Oxygen (and sometimes Fuel)

Symptoms that indicate a wheel assembly (tire and rim) has an uneven distribution of weight.

• Front wheel imbalance: vibration in steering wheel
• Rear wheel imbalance: vibration in seat/floorboard
• Vibration often occurs at specific speed ranges

Memory trick: Steering = Front, Seat = Rear.

An alignment condition where the rear wheels are not parallel to the vehicle's centerline, causing the vehicle to 'crab walk'.

• Causes a pull or dog tracking (vehicle drives crookedly)
• Often due to bent rear axle, damaged control arms, or misaligned subframe
• Can be non-adjustable on many solid axle vehicles

Memory trick: If front is good, look to the rear.

A condition where the starter motor continues to operate even after the ignition key is released from the 'START' position, typically due to welded contacts or a continuously energized solenoid.

• Starter motor runs continuously after key release.
• Indicates an issue with the starter solenoid.
• Can drain battery and damage starter/flywheel.

Memory trick: Key released, but the starter won't 'let go' – it's stuck!

A state where the charging system fails to provide adequate voltage (typically below 13.5V) to recharge the battery and power the vehicle's electrical components while the engine is running.

• System voltage remains at or near battery voltage (e.g., 12.0V).
• Occurs with engine running and accessories on.
• Primary cause is often a faulty alternator or voltage regulator.

Memory trick: If the 'power pump' isn't pushing voltage, the battery's just sitting there.

Failure of the flexible joint that transmits power from the transaxle to the wheels at a constant speed, allowing for suspension travel and steering.

• Common in front-wheel-drive vehicles
• Symptoms include clicking/grinding noise during turns
• Often caused by torn boots allowing dirt/moisture in

Memory trick: Turning sounds often point to axles.

A small radiator that transfers heat from the engine's hot coolant to the cabin air.

• Part of the engine's cooling system.
• Hot coolant flows through its tubes.
• A fan blows air across its fins to heat the cabin.

Memory trick: Coolant Flow is Key to Glow!

A condition where an automatic transmission takes an unusually long time to engage into Drive or Reverse, particularly noticeable when the engine and transmission are cold.

• Often hydraulic pressure related.
• Worsens with cold, thicker fluid.
• Can be caused by valve body issues or low fluid.

Memory trick: Cold, slow engagement means the pressure's low, like a sleepy bear after winter.

Diagnosing a wheel speed sensor circuit malfunction typically begins with a visual inspection of the sensor and its wiring for physical damage or disconnections, as these are frequent causes.

• DTCs often point to a specific sensor location.
• Visual inspection is a primary diagnostic step for electrical circuit faults.
• Physical damage or corrosion can cause circuit malfunctions.

Memory trick: When the ABS light glows, start by looking where the sensor goes!