OpenExamsFREE PRACTICE — ANY EXAM

ASE School Bus Brakes (S4) Certification — Requirements & Free Practice

US · License preparation

100 free questions · Answer explanations · No signup required

Loading selected examination banks…

Choose what to practice

Start with an exam below. Your examination requirements depend on your application pathway. View licensing requirements

Licenses, application pathways and examination requirements

Each license and applicant pathway has its own requirements and exemptions. Choosing practice questions does not determine your eligibility.

ASE School Bus Brakes (S4) Certification

Voluntary ASE certification in School Bus Brakes (S4), earned by passing the S4 initial certification test and satisfying ASE's relevant work-experience requirement or approved substitutions.

Licensing authority: National Institute for Automotive Service Excellence

Initial by examination
ASE School Bus Brakes (S4) Examination
Advanced Level
L3/L4 are separate advanced-level examinations, outside this S4 initial-certification task; no L3/L4 examination is inserted into this S4 route. The three-year/advanced-level requirements in the experience table apply to the named L tests, while the S1–S7 row establishes S4's two-year rule.
Applicability
Current official School Bus page adopts the fetched 2026 School Bus guide for the currently offered S4 initial examination; it redirects to the current SchoolBus_Study_Guide.pdf. No official beginning or ending date for this version, route or credential was published in the adopted materials, so date boundaries remain null. Document year/revision and retrieval date are not effective dates. This is voluntary nationwide certification, not a finding of nationwide statutory practice authority. No state groups were requested.
Education Substitutions
For the two-year Repair Technician requirement, choose one substitute; substitutes cannot be combined: (1) completion of an ASE-accredited Auto, M/H Truck or Collision-Refinish program, including MLR, AST, MAST and other current or grandfathered standards, gives one year credit; (2) completion of an ASE-accredited OEM-sponsored co-op program gives two years credit; (3) passing three or more different ASE Entry-Level Certification Program Tests gives one year credit; (4) other training gives one month credit per two months of full-time training or 200 program hours, up to one year. Remaining experience may be hands-on work. For (1)/(2), complete the whole program while it is ASE-accredited; co-op requires its hands-on work portion. Submit program completion certificates for (1)/(2), Entry-Level certificates for (3), and an official transcript showing completed hours/weeks and completion date for (4). Entry-Level tests are training-substitution qualifications, not additional S4 examination leaves.
Instructor Alternative
Four academic years of full-time instructor teaching (not teaching assistant), or part-time equivalent, in a high school/post-secondary Auto, M/H Truck or Collision-Refinish program plus at least 20 hours of technical update training in the last 12 months satisfies the corresponding two-year requirement. This alternative cannot combine with traditional hands-on experience or the formal-education substitutions. Attach a principal/dean-signed school letter detailing teaching experience and the technical update records, using Other Documentation.
Other Experience Credit
Current I-CAR Platinum status satisfies the two-year Repair Technician requirement corresponding to the role, with a current certificate. Veterans/active military submit DD Form 2586 (VMET), DD Form 214 or JST; qualifying MOS experience is evaluated. A valid Canadian provincial automotive trade certificate is accepted for the Repair Technician one-/two-year requirement with current license copy. Self-employment credit requires owner/operator work performing diagnosis and repairs in a licensed repair business, with service details, duration and current business license; home-garage repairs do not qualify. ASE retains discretion to evaluate all substitutions and other relevant experience.
Scheduling
Initial S4 requires a computer-based appointment at a Prometric test center. Purchase in myASE with applicable registration and test fees; schedule and complete testing within 90 days of purchase. Testing is available year-round. Present acceptable original unexpired government-issued photo/signature ID matching the myASE legal name. The general remote option is for recertification and initial G1, not initial S4.
Scope
S4 initial certification only; not Master School Bus Technician status, student certification or recertification. Passing S4 is the identified examination dependency; relevant experience is a separate certification condition.
Work Experience
Two years full-time (or part-time equivalent) of relevant Repair Technician hands-on experience maintaining, servicing and/or repairing light-duty or heavy-duty motor vehicles. Tests may be taken before meeting experience, but passing alone gives a score report and certification is withheld until experience is fulfilled and documentation approved. Create a personal myASE profile/ASE ID and submit the experience form and applicable supporting records for ASE review.

ASE School Bus Brakes (S4) Examination

Provider
Prometric test centers
Format
English computer-based, single-correct-answer multiple-choice initial certification examination at a test center.
Exam questions
Total questions: 60; Scored questions: 50; Unscored questions: 10; The total includes the scored and unscored questions.
Time limit
75 minutes
Examination outline
  • Air Brakes Diagnosis and Repair (68%)
    • Air Supply and Service Systems
    • Mechanical/Foundation
    • Parking Brakes
  • Hydraulic Brakes Diagnosis and Repair (20%)
    • Hydraulic System
    • Mechanical System
    • Power Assist Units and Miscellaneous
  • Antilock Brake System (ABS), Automatic Traction Control (ATC), Electronic Stability Control (ESC), and Collision Warning/Avoidance System Diagnosis and Repair (12%)
Examination sources