What are the responsibilities and job description for the Diagnostic Diesel Mechanic position at Merx Truck & Trailer, Inc.?
Merx Truck & Trailer is a high-velocity heavy-duty repair shop serving commercial fleets.
What You’ll Do
- Diagnose engine, transmission, aftertreatment, and chassis faults using OEM and aftermarket diagnostic software (Cummins INSITE, Detroit DiagnosticLink, PACCAR Davie, Volvo PTT, Allison DOC, Cat ET, JPRO, Noregon)
- Troubleshoot complex electrical systems - wiring harnesses, sensors, actuators, relays, control modules
- Read and interpret wiring diagrams, schematics, and fault code trees
- Diagnose CAN bus / J1939 network issues and ECM/ECU communication faults
- Perform live data analysis, active tests, forced regens, parameter programming, and ECM flashes
- Diagnose and repair aftertreatment systems (DPF, DEF, EGR, SCR)
- Use multimeters, oscilloscopes, and pressure transducers to isolate root cause
- Write clear, accurate repair scopes and hand off to repair techs with precise direction
- Some wrenching involved, but limited amount
- Road test and verify repairs before release
What We’re Looking For
- 3 years experience diagnosing heavy-duty diesel trucks (Class 7/8)
- Proficient with OEM diagnostic software across at least 3 major platforms (Cummins, Detroit, PACCAR, Volvo, Cat, International)
- Strong electrical troubleshooting skills — comfortable with schematics, multimeters, and oscilloscopes
- Solid understanding of J1939/CAN networks, ECMs, sensor circuits, and module communication
- Working knowledge of aftertreatment systems (DPF/DEF/SCR/EGR) and emissions diagnostics
What we offer
- $40–$55/hour base
- Consistent workflow - no waiting on jobs
- Latest diagnostic software, scan tools, laptops, and equipment provided
- Path to lead diagnostic tech and multi-location growth opportunities
- 401(k), 401(k) matching, PTO
Apply today
- Reach out at , or call Mike Allaway at 847-378-5528
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Pay: $45.00 - $55.00 per hour
Benefits:
- 401(k)
- 401(k) matching
- Paid time off
Work Location: In person
Salary : $40 - $55