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ASE Electronic Diesel Engine Diagnosis Specialist Test (L2)

Objective: To identify those technicians who possess knowledge of the skills necessary to diagnose sophisticated diesel engine performance problems on medium- and heavy-duty trucks.

Scope of Program: The Electronic Diesel Engine Diagnosis Specialist (L2) test consists of questions that test technicians' diagnostic knowledge of diesel engine mechanical and computer-controlled fuel systems. Questions cover both generic diesel engine systems, as well as three specific types of electronic diesel fuel control systems.

Test Development: The questions that appear on the Electronic Diesel Engine Diagnosis Specialist Test are written and approved by industry experts familiar with all aspects of electronic diesel engine diagnostics. Many of the questions relate to a sample vehicle equipped with the composite diesel engine control system. This system represents a cross section of electronic diesel engine control technology used by all engine manufacturers. This testing methodology assures an equal opportunity for all technicians who take the test, without bias towards any specific manufacturer.

Format: The scored portion of the test consists of 45 multiple-choice questions that address five content areas: General Diesel Engine Diagnosis, Electronic Diesel Engine Controls Diagnosis, Diesel Engine Air Induction and Exhaust Systems Diagnosis, Diesel Fuel Systems Diagnosis, and Specific Fuel Systems Diagnosis. The content area on Specific Fuel Systems Diagnosis includes six questions that separately address Electronic Unit Injector (EUI), Pump-Line-Nozzle-Electronic (PLN-E), and Hydraulic Electronic Unit Injector (HEUI) fuel systems. Some of the questions in the other content areas require extensive use of Composite Diesel Vehicle reference materials that are provided both upon registration and at the time of testing. The test may contain up to ten additional questions that are included for statistical research purposes only. Answers to these questions do not affect a technicians test score. Because of this test’s depth and scope, ASE recommends that technicians NOT register for other tests offered the same night.

Prerequisite: Those registering for the Electronic Diesel Engine Diagnosis Specialist Test must be currently certified in the regular Diesel Engines (S2 or T2) and Electrical/Electronic Systems (S6 or T6) test categories, and satisfy the two-year hands-on experience requirement.

Certification Requirements: To become ASE certified as a Electronic Diesel Engine Diagnosis Specialist, technicians must be currently certified in S2 or T2 and S6 or T6 and pass the Electronic Diesel Engine Diagnosis Specialist (L2) test.

Recognition: Those who earn L2 certification will be issued wallet and wall credentials, plus an appropriate shoulder insignia and a special toolbox plate. They will also receive ASE’s Blue Seal Tech News.

Recertification: To remain certified, technicians must be retested every five years.  This requirement ensures ASE-certified technicians are staying current with changes in the industry.  Those registering for the L2 recertification test must be currently certified in S2 or T2 and S6 or T6.

Fees: There is a $32 non-refundable registration fee per person, plus a $52 test fee for the L2 test. There is a $70 registration fee and a $74 test fee to take the computer-based L2 test.  All computer-based testing fees are non-refundable.

Registration: The Electronic Diesel Engine Diagnosis Specialist test is available in either Paper/Pencil or Computer-Based Testing format.

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