The GHG17 aftertreatment system (ATS) is a crucial component of DD platform vehicles, ensuring compliance with emission regulations. This airless dosing system utilizes Selective Catalytic Reduction (SCR) technology to convert harmful nitrogen oxides (NOx) into harmless substances. This guide provides a detailed overview of the GHG17 ATS, its components, and functionality, serving as a valuable resource for technicians seeking a comprehensive Dd Platform Workshop Manual.
The SCR system within the GHG17 ATS comprises several key components: an Aftertreatment Control Module (ACM), a Diesel Exhaust Fluid (DEF) tank, a DEF pump, an airless DEF dosing unit, and the SCR module itself. The system operates by pumping DEF at high pressure (10 bar/145 psi) to the dosing unit. This unit then atomizes the DEF into a fine mist and injects it into the SCR module. Inside the module, a chemical reaction occurs, converting NOx in the exhaust stream into water vapor and nitrogen.
A notable change in the GHG17 1-BOX™ ATS configuration is the elimination of the SCR inlet temperature and Diesel Particulate Filter (DPF) outlet pressure sensors. Replacing these sensors is a Soot Probe, directly connected to a newly added Sensor Control Unit (SCU).
Fig. 1: Soot Probe and Sensor Control Unit (SCU) on the DD Platform
The GHG17 platform retains Hydrocarbon (HC) dosing for regeneration during over-the-road driving. The DEF-to-fuel ratio remains around 4.3%. However, due to adjustments in the fueling strategy, drivers might observe a change in engine noise during HC dosing on DD13 and DD15 platforms. This is a normal operating characteristic and not a cause for concern. Consulting a dd platform workshop manual for specific details related to your engine model is recommended.
Fig. 2: GHG17 1-BOX™ Configuration Diagram for DD Platform
The diagram above illustrates the key components of the GHG17 1-BOX™ configuration. Understanding the location and function of each component is crucial for effective diagnostics and repair. Referencing a detailed dd platform workshop manual can provide further insights into specific system operations and troubleshooting procedures. The GHG17 system, with its advanced SCR technology, plays a critical role in minimizing emissions and ensuring the environmental performance of DD platform vehicles. Familiarizing oneself with its intricacies is essential for any technician working on these vehicles.
