ASE G1 study guide
ASE G1 · Work through your exam, one topic at a time.
ASE G1, part of the ASE Certification Test Series administered by the National Institute for Automotive Service Excellence, is a multiple-choice credential for automotive service professionals who perform maintenance and light repair work - the routine services and inspections that make up a large share of everyday shop traffic. It is aimed at technicians early in their careers, at entry-level graduates moving into a dealership or independent shop, and at working techs who want a single credential that documents broad, practical competency rather than deep specialization. The ASE G1 study guide has 8 sections and about 2,896 words.
01Engine Systems
G1 engine work is inspection and service, not overhaul. You must know the lubrication path (pickup, pump, filter, galleries, drain-back), the cooling path (water pump, thermostat, radiator, hoses, pressure cap, fan, recovery bottle), the induction path (air filter, duct, throttle body, PCV/breather), and the accessory drive (serpentine belt, tensioner, idlers, mounts, seals).
336 words, about 2 min02Automatic Transmission and Transaxle
On the G1 you check condition and fluid, perform routine services, and recognize symptoms that condemn a unit. Know the major parts: torque converter with its clutch, pump, valve body, shift solenoids, clutch packs, planetary gearsets, final drive (transaxle), TCM, cooler lines, mounts.
392 words, about 2 min03Manual Drive Train and Axles
This domain covers the clutch and its hydraulics, manual transaxles and transmissions, CV axles and boots, driveshafts and universal joints, differentials, transfer cases, and wheel-end components. The G1 expects inspection and service competence plus the ability to link a noise or vibration to a specific component.
367 words, about 2 min04Suspension and Steering
The G1 tests inspection and replacement of worn parts plus a working understanding of alignment angles. Know struts and shocks, coil and leaf springs, control arms and bushings, ball joints, tie rods, sway bar links, steering racks, electric power steering, and hub bearings.
360 words, about 2 min05Brakes
Brake work on the G1 covers inspection, pad and rotor replacement, caliper service, hose and line condition, drum brakes, parking brakes, ABS components, and hydraulic diagnosis. Safety and cleanliness matter as much as diagnosis.
359 words, about 2 min06Electrical and Electronic Systems
Expect battery, starting, and charging service plus basic circuit diagnosis with a digital multimeter. You should be comfortable with Ohm's law, series and parallel circuits, fuses and relays, grounds, voltage drop testing, parasitic draw, and module communication basics.
353 words, about 2 min07Heating, Ventilation, and Air Conditioning
The G1 covers A/C inspection and routine service, heater performance, and air distribution. You must know the refrigerant circuit: compressor, condenser, receiver-drier or accumulator, expansion device, evaporator, and the controls that move air.
356 words, about 2 min08Engine Performance
Engine performance questions test diagnostic reasoning more than memorized specs. Know OBD-II monitors and readiness, DTC structure, freeze frame and live data, fuel trim, misfire diagnosis, and the basic air, fuel, and spark requirements.
373 words, about 2 min