ASE G1 Auto Maintenance and Light Repair flashcards

A blockage or malfunction within the expansion valve that impedes the flow of refrigerant into the evaporator, significantly impacting AC system performance.

• Causes high low-side pressure and low high-side pressure.
• Results in poor or no cooling.
• Can be identified by temperature differences across the valve.

Memory trick: Pressure Puzzles Pinpoint Problems.

Signs of a worn serpentine belt include glazing (shiny surface), cracking, fraying, and missing ribs, all indicating a loss of material integrity and requiring replacement.

• Glazing reduces friction and grip.
• Cracks indicate material fatigue.
• Worn belts can slip or break, stopping accessories.

Memory trick: Cracked and glazed, the belt's days are phased.

A thermostat stuck in the open position prevents the engine from reaching its optimal operating temperature, leading to symptoms like a consistently cold temperature gauge, poor fuel economy, and insufficient cabin heat.

• Engine runs 'too cold'.
• Gauge reads low, even after warm-up.
• Heater often doesn't work well.
• Increases emissions and reduces fuel economy.

Memory trick: Cold gauge, no heat, thermostat's stuck open, can't be beat.

Common issues that lead to an automotive heating system failing to produce adequate warmth, despite the engine operating at normal temperature.

• Air pockets in the heater core are a frequent cause.
• Can also be caused by blend door issues, clogged heater core.
• Normal engine temperature differentiates from thermostat issues.

Memory trick: Heater's Hopes Hinder with Hidden Air.

When drum brake linings and drums are severely worn or damaged, both components must be replaced to restore proper braking function.

• Check drum diameter against specification
• Replace shoes if worn or contaminated
• Replace drums if grooved or beyond service limit

Memory trick: Groovy drums and worn shoes mean a full replacement is due.

When an engine cranks, receives fuel (wet plugs), but has no spark, the issue is typically in the primary ignition circuit, often a failed crankshaft position sensor or an issue with the ignition control module/ECM.

• Wet plugs = fuel delivery is good.
• No spark = ignition system fault.
• Crank sensor is crucial for spark timing.

Memory trick: No spark, fuel's fine, crank sensor's out of time.

The electrical path that allows an automotive blower motor to operate at its maximum speed, often bypassing the resistor block and using a dedicated relay.

• Highest speed typically bypasses the resistor block.
• Often controlled by a separate, dedicated relay.
• Failure of this relay results in loss of only the highest speed.

Memory trick: Resistor for Rests, Relay for Rush.

The presence of coolant in engine oil typically results in a milky, frothy, or 'milkshake' appearance of the oil, often accompanied by engine overheating or coolant loss.

• Milky oil indicates coolant contamination.
• Often caused by head gasket failure.
• Coolant level usually drops.

Memory trick: Milky oil is coolant's foil.

The correct procedure for replacing an engine oil filter to ensure proper sealing and function.

• Always use the correct filter for the application.
• Lubricate the gasket before installation.
• Tighten to specification (hand-tight plus a quarter to half turn, or torque wrench).
• Check for leaks after engine startup.

Memory trick: New filter: prep the seal, then tighten and check.

Symptoms of a failing water pump include engine overheating, visible coolant leaks from the pump, and sometimes a whining noise from the pump pulley.

• Primary function is coolant circulation.
• Failure causes overheating due to lack of flow.
• Hot upper hose, cool lower hose is a key indicator.

Memory trick: Hot top, cold bottom, no flow, pump's rotten.

Visual and tactile examination of a serpentine belt for signs of wear, damage, and proper tension to ensure reliable operation of engine accessories.

• Cracks, fraying, missing ribs, or glazing are signs of wear.
• Proper tension is crucial for preventing slippage and component damage.
• A worn belt can lead to loss of power steering, alternator, or A/C.

Memory trick: Look for the edges fraying or ribs disappearing, that's when it's time to change.

Play detected at the steering gearbox, with tight external connections, indicates internal wear or excessive lash within the steering gearbox itself.

• Play between input and output.
• External linkages are tight.
• Requires gearbox adjustment or replacement.

Memory trick: Gearbox Play, No Other Way, If Pitman's Tight, Gearbox's Plight.

Squealing noises from the serpentine belt can be caused by the belt itself (worn, loose) or by a failing accessory component it drives.

• Belt slipping on pulleys creates the noise.
• Causes: worn belt, loose tensioner, failing accessory (alternator, A/C compressor, power steering pump).
• Often worse when cold or under load (e.g., turning).

Memory trick: Belt squeals, two tales: belt's worn or pump fails!

When an ABS warning light is on and a specific DTC is retrieved, the first diagnostic step is to visually inspect the component and wiring indicated by the code.

• DTCs guide diagnosis
• Visual inspection first
• Check connectors and wiring

Memory trick: Code points the way, inspect it today!

Excessive, prolonged bouncing of the vehicle after hitting a bump or being manually compressed indicates worn or failing shock absorbers.

• Shocks dampen spring oscillations.
• Prevents continuous bouncing.
• Affects ride comfort and tire contact.

Memory trick: Bouncy Ride? Shocks Can't Hide!

A brief illumination of the ABS warning light during vehicle startup, indicating that the ABS control module is performing a diagnostic check of its components.

• Normal behavior if the light turns off afterward.
• If the light stays on, it indicates a fault in the ABS system.
• If the light never illuminates, it could indicate a bulb or circuit fault.

Memory trick: A quick flash means all systems are a-OK!

A broken timing belt or chain causes immediate and severe engine issues, including sudden power loss, loud mechanical noises, and potentially catastrophic internal engine damage.

• Synchronizes crankshaft and camshaft rotation.
• Failure leads to incorrect valve timing.
• Common symptoms: sudden engine stall, loud popping/crunching, no-start condition.
• Can result in bent valves or damaged pistons in interference engines.

Memory trick: Loud pop, smoke, no go? Timing belt's gone, oh no!

Distinctive visual indicators used to identify the R-1234yf refrigerant type in an automotive AC system, crucial for preventing cross-contamination.

• Uses unique 'green' service port caps and fittings.
• Designed to prevent accidental mixing with other refrigerants.
• A newer, lower Global Warming Potential (GWP) refrigerant.

Memory trick: Green's Good for the new Generation.

A drum brake self-adjuster automatically maintains optimal shoe-to-drum clearance; if seized in an over-adjusted state, it causes premature brake engagement and 'grabbiness.'

• Maintains shoe clearance
• Seized adjusters cause issues
• Over-adjustment leads to grabby brakes

Memory trick: Adjuster seized, grabby and tight, fix the adjuster to make it right!

The stabilizer bar (sway bar) reduces body roll during cornering by transferring suspension load from the heavily loaded side to the lightly loaded side.

• Connects the left and right suspension components.
• Worn bushings or links compromise its effectiveness.
• A properly functioning stabilizer bar improves handling and stability.

Memory trick: Roll and sway, bushings give way.

For MVAC systems opened for service, EPA Section 609 requires evacuation to a full vacuum (29.92 inches Hg) to remove all air and moisture.

• Removes non-condensable gases (air).
• Boils off moisture at lower temperatures.
• Prevents acid formation and system damage.
• Crucial for system efficiency and longevity.

Memory trick: Full vacuum is the rule, for a system that's cool.

A ruptured brake hose causes a sudden, complete loss of hydraulic pressure in one circuit, leading to the brake pedal going to the floor and potentially a burning fluid smell.

• Sudden pedal loss
• Complete loss of pressure
• Burning fluid smell possible

Memory trick: Pedal to the floor, burning smell, a ruptured hose casts its spell.

Standard color coding for automotive AC manifold gauge hoses: Blue for low-side, Red for high-side, Yellow for vacuum/charge port.

• Blue = Low-side service port.
• Red = High-side service port.
• Yellow = Center port (vacuum pump/refrigerant source).
• Prevents cross-contamination and incorrect connections.

Memory trick: Red is hot, Blue is cool, Yellow fills the tool.

Excessive free play in the steering wheel of a vehicle with a recirculating ball steering gear, when other components are sound, often indicates internal wear or improper adjustment of the steering gearbox itself.

• Common in older trucks/SUVs.
• Internal wear or adjustment issues.
• Causes excessive steering wheel play.

Memory trick: Loose steering wheel, no other faults, means the 'gear' itself is out of sorts.

Personal Protective Equipment (PPE) like safety glasses and gloves are crucial when handling refrigerants to prevent frostbite and eye injury.

• Liquid refrigerant causes severe frostbite on skin contact.
• Refrigerant splashes can cause permanent eye damage.
• Safety glasses (or face shield) and protective gloves are mandatory.
• Work in well-ventilated areas.

Memory trick: Eyes and hands first, when the cold stuff bursts.

The condenser is a heat exchanger that converts high-pressure refrigerant vapor into high-pressure liquid by releasing heat to the surrounding air.

• Located on the high-pressure side of the system.
• Usually in front of the radiator.
• Facilitates heat transfer from refrigerant to ambient air.
• Essential for the phase change from vapor to liquid.

Memory trick: Condenser cools down, evaporator cools in.

The condenser cooling fan provides airflow over the condenser, especially at low vehicle speeds, to ensure efficient heat dissipation and proper AC system operation.

• Crucial for AC performance at idle and low speeds.
• Helps convert high-pressure vapor to high-pressure liquid.
• Malfunction leads to high head pressure and poor cooling.

Memory trick: Idle warm means the fan's not doing its part, letting the condenser get hot at the start.

A common engine noise caused by insufficient oil pressure or worn components within hydraulic valve lifters, often characterized by a tapping or clicking sound.

• Often louder when the engine is cold and quiets as it warms up.
• Caused by oil draining from lifters or insufficient oil pressure.
• Can be a sign of low oil level, dirty oil, or worn lifters.

Memory trick: A 'TAPPING' lifter loves 'COLD' starts but 'QUIETS' down with 'WARM' oil.

The receiver/drier stores liquid refrigerant and, more importantly, removes moisture and filters contaminants from the system.

• Located in the high-pressure side after the condenser.
• Contains a desiccant to absorb moisture.
• Contains a filter to remove particulate contaminants.

Memory trick: The drier keeps it clean and dry, so the AC can fly.

A harsh, metal-on-metal sound heard during braking, typically indicating severely worn brake pads allowing the backing plate to contact the rotor.

• Often accompanied by reduced braking performance.
• Requires immediate inspection and replacement of worn components.
• Can lead to rotor damage, requiring resurfacing or replacement.

Memory trick: Brake noises tell a story; grinding means metal is meeting metal.

A common cause of a sulfur-like (rotten egg) smell from vehicle exhaust, indicating the converter is not properly processing exhaust gases.

• Converts harmful pollutants into less toxic ones.
• Sulfur smell often due to incomplete conversion of hydrogen sulfide.
• Can also cause reduced engine performance or a 'check engine' light.

Memory trick: Smelly exhaust, it's a 'cat'astrophe!

Signs of degradation in a serpentine belt, such as cracking, fraying, or glazing, which indicate reduced effectiveness and the need for replacement.

• Cracks on the ribbed side are a primary indicator of wear.
• Glazing (a shiny, hardened surface) reduces grip.
• A worn belt can lead to accessory slippage and failure.

Memory trick: Belt 'CRACKS' and 'GLAZES'? It's time for a 'CHANGE'!

Caliper piston seizure, often caused by internal corrosion from contaminated brake fluid, leads to constant brake drag, excessive heat, and decreased fuel economy.

• Corrosion from water in fluid
• Piston fails to retract
• Causes drag, heat, burning smell

Memory trick: Drag and heat, burning scent? Fluid's corroded, the piston's spent!

A failure in the brake booster system, which is designed to multiply the force applied to the brake pedal, resulting in a significantly harder pedal feel and increased stopping distances.

• Vacuum or hydraulic assist mechanism
• Reduces driver effort for braking
• Malfunction leads to hard pedal and poor stopping

Memory trick: Hard Pedal, Slow Stop: Boost Gone!

Symptoms of a fuel system leak include a strong gasoline odor, visible fuel drips or puddles, and potentially a decrease in fuel economy.

• Strong gasoline smell is a primary indicator.
• Visible fuel on the ground confirms a leak.
• Leaks can occur in lines, tank, or injectors.

Memory trick: Smell Gas, See Puddle, Find the Source.

Worn or loose stabilizer bar links are a frequent cause of clunking or rattling sounds in the suspension, especially when driving over uneven surfaces.

• Connects the stabilizer bar to the control arm or strut.
• Contains bushings or ball joints that can wear out.
• Replacement often resolves suspension noise issues.

Memory trick: Clunking on bumps often means a link is loose.

Incorrect toe setting causes tires to scrub sideways as they roll, leading to rapid and uneven wear on the inner or outer edges of the tread.

• Toe-in means the front of the wheels are closer together than the rear.
• Toe-out means the front of the wheels are further apart than the rear.
• Excessive toe-in causes outer edge wear; excessive toe-out causes inner edge wear.

Memory trick: Toe's scrub wears the tire's edge.

A localized area of excessive wear on a tire's tread, often caused by sustained braking or a mechanical issue, leading to a rhythmic thumping noise.

• Causes rhythmic thumping noise.
• Increases with vehicle speed.
• Often due to braking issues or prolonged parking.

Memory trick: Flat tires cause a thump, think 'brake' for the bump.

A crack in the exhaust manifold can cause an exhaust leak, leading to increased noise and, critically, affecting upstream oxygen sensor readings.

• Introduces unmetered air into exhaust stream.
• O2 sensor reads false lean, causing ECU to enrich mixture.
• 'Check Engine' light common (fuel trim/O2 sensor codes).
• Increased exhaust noise and potential power loss.

Memory trick: Crack in the manifold? O2 sensor's plan is canned!

Correct vehicle ride height is crucial for accurate wheel alignment measurements, as suspension geometry is designed to function optimally at its specified height.

• Uneven or incorrect ride height distorts camber and toe angles.
• Suspension components like springs or shocks affect ride height.
• Ride height must be checked and corrected before performing an alignment.

Memory trick: Level ground, level car, level readings.

Signs of a failing catalytic converter include a 'rotten egg' smell from the exhaust, reduced engine performance, decreased fuel efficiency, and an illuminated Check Engine Light.

• Converts harmful exhaust gases.
• Sulfur smell is a key indicator of failure.
• Can cause power loss and fuel economy issues.

Memory trick: Rotten eggs mean the cat's gone bad.

Brake bleeding removes air from the hydraulic system to restore a firm pedal, typically done by forcing fluid through the system from the master cylinder to each wheel, starting furthest away.

• Removes air bubbles
• Restores firm pedal
• Start furthest from master cylinder

Memory trick: Pressure the fluid, push the air out, furthest first, no doubt!

If a fuel pump primes but no fuel pressure is detected at the rail, it often indicates a significant leak or rupture within the fuel tank itself, preventing pressure from building in the fuel delivery lines.

• Pump priming means it gets power.
• No pressure with priming indicates an internal leak.
• Ruptured in-tank line is a common culprit.

Memory trick: Pump hums, no pressure, in-tank rupture is the stressor.

A Diagnostic Trouble Code indicating a detected leak in the Evaporative Emission Control System, often caused by a loose fuel cap or a small crack in a vacuum hose.

• Often triggered by a loose, missing, or faulty fuel cap.
• Results in a gasoline smell due to vapor escape.
• The EVAP system captures fuel vapors to prevent release into the atmosphere.

Memory trick: A 'LOOSE CAP' lets 'GAS' vapors 'ESCAPE' and triggers 'P0442'.

Parking brake effectiveness relies on proper adjustment, sufficient shoe lining, and un-stretched cables to ensure adequate holding force.

• Mechanical operation, separate from hydraulics
• Worn shoes reduce holding power
• Stretched cables prevent full engagement

Memory trick: Shoes or cables worn, the parking brake is forlorn.

A collapsed or worn hydraulic lifter (tappet) causes a distinct ticking or tapping sound from the top of the engine, often more noticeable on cold starts due to insufficient oil pressure or worn components.

• Noise comes from the top of the engine.
• Often worse when cold, improves as oil pressure builds.
• Indicates insufficient oil to lifter or lifter wear.
• Affects valve lash and can reduce engine efficiency.

Memory trick: Top tick, cold start, lifter's playing a noisy part.

The blower motor resistor regulates the current flow to the blower motor to provide different fan speeds, with the 'HIGH' setting often bypassing it.

• Creates resistance to reduce motor speed.
• Usually located in the blower motor housing/ductwork.
• Can fail due to overheating, causing loss of lower speeds.
• 'HIGH' speed typically gets full voltage, bypassing resistor.

Memory trick: Low speeds are gone, resistor's undone, but HIGH keeps on.

A diagnostic trouble code indicating an electrical fault with the motor or wiring responsible for actuating an electronic parking brake caliper.

• EPB systems use electric motors at the calipers, not cables.
• The fault points to an issue with the motor's power supply, ground, or control signal.
• Requires electrical testing of the motor and its associated wiring harness.

Memory trick: EPB motor circuit fault means the electric gears aren't turning.

Specific procedures and precautions required to safely work on the high-voltage components of hybrid and electric vehicles.

• High voltage systems can deliver lethal shocks.
• Always wear appropriate PPE, including insulated gloves.
• The primary safety step is to disable the high-voltage system via its service disconnect.
• Verify system is de-energized before beginning work.

Memory trick: Before touching the power, pull the plug to prevent a shock.

A condition where a vehicle veers to one side during braking, typically caused by an imbalance in braking force between the left and right wheels.

• Most often due to a seized caliper, contaminated pad, or air in the line on one side.
• The vehicle pulls towards the side that is braking effectively.
• Requires inspection of all brake components on the affected axle.

Memory trick: Brake pull means an imbalance, like a wonky scale.

Visual and auditory signs that exhaust gases are escaping the exhaust system at an unintended point, often due to a compromised seal or crack.

• Sooty black residue around joints or cracks is a primary visual indicator.
• Audible 'hissing' or 'tapping' noise, especially when cold.
• Can lead to exhaust fumes entering the cabin.

Memory trick: Black 'SOOT' on the 'PIPE' means a 'LEAK' is near!

Diagnostic Trouble Code indicating that the engine's fuel-air mixture is excessively rich (too much fuel, not enough air) in Bank 1, often leading to black smoke and poor performance.

• Indicates an excess of fuel in the combustion process.
• Common symptoms include black smoke, reduced fuel economy, and rough running.
• Can be caused by leaking injectors, high fuel pressure, or faulty sensors.

Memory trick: Too much 'FUEL' makes the engine 'SMOKE' with 'P0172'!

The proper adjustment of drum brake shoes to maintain a minimal clearance with the drum is crucial for correct brake pedal height and feel.

• Excessive shoe-to-drum clearance causes a low brake pedal.
• Drum brakes often have self-adjusters that can fail or need manual adjustment after service.
• Proper adjustment ensures the master cylinder doesn't have to over-travel to build pressure.

Memory trick: Low and firm means the shoes are too far, not spongy air.

A common failure point in drum brake systems where hydraulic fluid leaks past the internal seals of the wheel cylinder, contaminating brake shoes.

• Causes reduced braking effectiveness and pull to one side.
• Contaminated shoes must be replaced, along with the leaking wheel cylinder.
• Fluid appears on the inside of the drum brake assembly.

Memory trick: The wheel cylinder weeps inside the drum, soaking the shoes.

EPA Section 609 requires technicians to be certified to purchase and handle refrigerants for Motor Vehicle Air Conditioning (MVAC) systems.

• Mandates training for proper refrigerant handling.
• Prevents harmful release of refrigerants.
• Applies to purchasing and servicing activities.
• Protects ozone layer and reduces climate impact.

Memory trick: Certify to buy, or the air will cry.

A brake booster failure results in a hard brake pedal requiring significantly more force to stop the vehicle, as the power assistance is lost.

• Increases pedal effort
• Often accompanied by a pull if other components are also failing
• Vacuum or hydraulic assist

Memory trick: Hard Pedal, Hard Stop, Hard to Ignore the Booster.

When an alignment angle is out of specification on a non-adjustable suspension, it almost always indicates a bent, worn, or damaged component requiring replacement.

• Rear suspension often has non-adjustable components.
• Out-of-spec angles imply physical damage, not just adjustment need.
• Requires thorough inspection for bent arms, worn bushings, or damaged mounting points.

Memory trick: No adjustment means damage, not just a tweak.

A P030X DTC (e.g., P0301, P0302) indicates a misfire in a specific cylinder, where X represents the cylinder number. P0300 indicates a random or multiple cylinder misfire.

• P030X indicates a specific cylinder misfire.
• P0300 indicates random/multiple misfires.
• Common causes are spark, fuel, or compression issues for that cylinder.

Memory trick: P0303: Cylinder 3, a misfire's key.

The recommended method for changing the position of tires on a front-wheel-drive vehicle to promote even wear and maximize tire lifespan.

• Specific patterns vary by drive type and tire type (directional vs. non-directional).
• FWD vehicles typically wear front tires faster due to steering, braking, and propulsion.
• A common FWD pattern involves moving front tires straight back and crossing rear tires to the front.

Memory trick: FWD: Fronts go straight back, rears cross to the front.

Troubleshooting a no-start condition where fuel injectors are not receiving electrical signals to open, despite other conditions like spark and fuel pressure being present.

• Indicates the ECM is not commanding fuel injection.
• Often points to a missing engine position signal (crankshaft/camshaft sensor).
• Can also be caused by ECM failure or wiring issues to injectors.

Memory trick: No 'PULSE' means the 'CRANK' sensor's gone 'MISSING'.