ASE certification — which tests to take first and how to schedule multiple certifications
I'm a shop tech with 6 years of experience and I'm finally getting serious about ASE certification. My shop owner has been after me to do it for two years and I've been putting it off because the exam schedule feels overwhelming when you look at all 9 of the A-series tests. I don't know whether to try a few at a time or just go for all 9 in one sitting.
My strongest areas are brakes (A5), electrical/electronics (A6), and suspension/steering (A4). My weakest are engine performance (A8) and automatic transmission (A2). I've been doing about 45 minutes of study a day for the past 5 weeks and my A5 practice scores are around 78–80%.
Has anyone done all 9 A-series in a single test window? Is that realistic or does it spread your prep too thin? I've got 10 weeks before the next test window and I'm trying to decide how many to attempt.
Also: how much does the A8 engine performance test actually cover OBD-II diagnostics and scan tool interpretation versus engine theory? My diagnostic skills are strong but my theory knowledge is patchier.
All 9 in one window is doable but really hard. Most serious techs I know do 3–5 per window—enough to make real progress without spreading prep too thin. With 10 weeks and 45 minutes a day, I'd target your 3 strongest (A4, A5, A6) this window and save A2 and A8 for the next one when you can give them full attention.
Your 78–80% on A5 practice means you're close to ready there. The A5 exam is one of the more straightforward in the series.
A8 engine performance is probably 50% OBD-II diagnostics and scan tool interpretation, 30% fuel and ignition systems, and 20% theory. Your strong diagnostic skills are directly relevant—the scan data interpretation questions (understanding mode 6, freeze frame, readiness monitors) are worth reviewing specifically since they show up in multiple forms.
A2 automatic transmission is one of the hardest in the series. Most experienced techs still need 8–10 weeks of dedicated prep for it. Don't underestimate it based on your bench experience.
I did 4 tests in my first window—A4, A5, A6, A7 (heating/air conditioning). Passed all four. The key was treating each test as its own isolated prep track and not letting the material bleed together.
For your situation I'd do A4, A5, and A6 this window. Clean sweep on those builds confidence, gets you three certifications, and positions you well for A8 and A2 with dedicated focus next window.