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How to Obtain an L2 ASE Study Guide and Practice Test

Ken Wolter /

When you’re first starting out in your mechanic career, it doesn’t take long to realize that the best way to get a good automotive technician job is by attaining Master Mechanic status. Getting ASE certified can boost your earnings potential, and make you more marketable to employers. You’ll need at least two years of experience first, but the extra effort is worth the payoff.

The National Institute for Automotive Service Excellence, or NIASE, is the governing body which tests and certifies mechanics in order to officially verify their skill level. There are over 40 areas of certification, including L2 which is the test to become an Electronic Diesel Engine Diagnosis Specialist. In order to gain this designation, you must first have passed one of the ASE Diesel Engine tests – A9, H2, S2, or T2 – and an Electrical/Electronic Systems test as well – A6, H6, S6, or T6.

The topics covered in the L2 test include diagnosis of:

  • General diesel engine
  • Electronic diesel engine controls
  • Diesel fuel systems
  • Diesel engine air induction and exhaust systems

There are plenty of resources available online to help you prepare, including L2 study guides and practice tests.

The ASE website

The NIASE website is a great resource for preparing for your L2 exam. There are free study guides for each area of expertise available on the Test Prep & Training page. In order to be properly prepared, you also need to download the Medium-Heavy Composite Vehicle Type 2 Reference Booklet, which is a study guide to be used prior to and during the test. This booklet deals with information on the composite diesel engine which is referred to in questions on the exam.

An L2 practice test is also available on the website, in addition to versions for each different certification. These work on a voucher system in which you purchase vouchers which give you a code, and then you use the code to access whichever practice test you need. Vouchers cost $14.95 each for the first one or two, $12.95 each if you buy between three and 24, and $11.95 each for 25 or more.

The practice version is half the length of the real test, and when you are finished you will receive a performance report, telling you which questions you got correct and which you got incorrect. Reviewing this feedback should help you figure out which specific areas you need to study further.

Third-party websites

When you are searching for ways to obtain an L2 study guide and practice test, you’ll quickly realize that there are many aftermarket resources available. It can be challenging to sort out which are useful and which not so much, so be sure to read testimonials. ASE does not endorse or review these programs, however they do maintain a list of companies on their website for informational purposes. Research your options carefully to be sure you’re getting a reputable program with accurate study information.

Taking the test

When you’re ready to take the actual test, there are plenty of options for scheduling. Testing is available 12 months out of the year, and weekend times are available as well. The NIASE provides information on their website regarding finding a testing location and scheduling your exam day. All of the testing is computer based, and there’s even a demo on the website so that you can get comfortable with the format before your scheduled day.

The L2 Advanced Engine Performance Specialist test contains 45 scored multiple choice questions, plus an additional 10 or more questions which are used for statistical data purposes only. The unscored questions are not marked as such, so you won’t know which questions count and which don’t. You will need to answer every question to the best of your knowledge.

The NIASE recommends avoiding scheduling any other testing for the day you take the L2, due to how complex the topic is. As long as you utilize study guides and practice tests and work hard to prepare for the big day, you should be able to attain L2 Master Technician status.

If you’re already a certified mechanic and you’re interested in working with YourMechanic, submit an online application for an opportunity to become a mobile mechanic.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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