DPF Service Regeneration: Soot Load to Clean Filter
John Deere 4045 · Level 34 ECU · Instructor-led class
The full system before the regen starts: soot at 94 %, every component labelled, live ECU data on the right.
About the class
A practical classroom session for diesel technicians on the Final Tier 4 exhaust aftertreatment system and the service (parked) regeneration. The class follows a loaded DPF from the regen request through thermal management, in-cylinder dosing, soot burn-off, SCR NOx conversion and cool-down. Each stage is tied to the live ECU data technicians will see on the service tool: T1-T4 temperatures, DPF ΔP, soot load, throttle positions, DEF pressure and NOx readings.
| 6 | 19 | For |
|---|---|---|
| Teaching modules, intro to review | Components traced and labelled | Diesel technicians and apprentices |
What technicians will be able to do
- Trace the exhaust from the turbo to the tailpipe and name every air-system and aftertreatment component.
- Explain how the ECU estimates soot load, and which interlocks must be met before a service regen starts.
- Describe how the intake throttle, EGR valve and exhaust throttle valve raise exhaust temperature, and why the 4045 doses fuel through in-cylinder post-injection.
- Read T1-T4, DPF ΔP and NOx 1 / NOx 2 live data, and calculate SCR conversion efficiency.
- Diagnose a failed or aborted regen in the right order: interlocks, air system, DOC, DPF, SCR.
Course outline
| Time | Module | Covers |
|---|---|---|
| 0:00 | Intro & safety | Objectives, exhaust heat and DEF hazards |
| 0:10 | 1 · System overview | Gas path, the 19 components and where they sit |
| 0:26 | 2 · Soot load & regen request | ΔP and the soot model, regen types, interlocks |
| 0:42 | 3 · Heat-up & dosing | Throttles, EGR, DOC light-off, post-injection |
| 1:00 | Break | 10 minutes |
| 1:10 | 4 · Soot burn & SCR | Oxidation, ash, DEF dosing, NOx efficiency, cool-down |
| 1:30 | 5 · Diagnostics | Live data on Service ADVISOR or Jaltest, four case scenarios |
| 1:50 | 6 · Review | Review quiz, key values, questions |
Interlocks and DOC heat-up
Service regen interlock checks
DOC exotherm heating the DPF
Soot oxidation and SCR conversion
Soot oxidizing in the DPF
SCR NOx conversion efficiency: (400 - 80) ÷ 400 × 100 = 80 %
What the class includes
Classroom slide deck
Concepts, key values, chemistry, four diagnostic scenarios and the review quiz.
Student workbook
Component labelling, interlock list, live-data logs, NOx efficiency worksheet and scenarios.
Instructor notes
Scene-by-scene talking points, key values, diagnostic tie-ins and quiz answers.
Students bring
- Service ADVISOR or Jaltest diagnostic tool with live-data access
- Student workbook (provided) and a pen
- PPE for the shop portion: safety glasses and heat-rated gloves
DEF dosing unit (A), line (C) and dosing injector (B)
Book this class
Need a custom track?
Combine Jaltest onboarding with emissions, electrical, or HPCR refreshers. We routinely build blended agendas for growing fleets and dealer networks.