Diesel Mechanic: CRD 
           - Mining Qualifications Authority - All rights reserved. 
                 DIESEL MECHANIC 
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                         CODE: CRD 
             COMMON RAIL DIESEL 
                            SYSTEMS 
                                        
        
        
        
        
        
        
       Created : March 2015                               First Published : March 2015 
       Revised : March 2015                                    Revision No: 001 
       Owner : Learnership Department                               TRG 9 
                                                                 Page 1 of 34 
              Diesel Mechanic: CRD 
               - Mining Qualifications Authority - All rights reserved. 
               
            
            
           The following elements are contained in this learning guide: 
                                          TOPIC                                    PAGE NUMBER 
           Index                                                                           2 
           Objective                                                                       3 
           Source reference                                                                4 
           Hazard Identification and Control (HIAC) form                                   5 
           Dictionary                                                                      6 
           Condition report                                                                7 
           Introduction to common rail diesel fuel system                                  9 
           Common rail circuits                                                           10 
           High pressure fuel pump                                                        12 
           Fuel metering control valve                                                    13 
           High pressure accumulator (common rail)                                        16 
           Fuel rail pressure sensor                                                      17 
           Rail pressure limiter valve                                                    19 
           Fuel rail pressure control valve solenoid                                      20 
           Rail pressure control valve failure symptoms and diagnosis                     22 
           Common rail fuel injectors                                                     23 
           Injector codes                                                                 27 
           Engine management closed loop control functions                                28 
           Injector leak back test                                                        30 
           Retrieving diagnostic trouble codes                                            31 
           Sensors                                                                        31 
           Practise                                                                       34 
            
            
            
            
            
            
            
            
            
            
           Created : March 2015                                                      First Published : March 2015 
           Revised : March 2015                                                             Revision No: 001 
           Owner : Learnership Department                                                          TRG 9 
                                                                                               Page 2 of 34 
                 Diesel Mechanic: CRD 
                  - Mining Qualifications Authority - All rights reserved. 
                  
             OBJECTIVE 
              
             WHAT YOU MUST DO 
              
             Given a common rail diesel engine you must be able to: 
              
                    Retrieve Diagnostic Trouble Codes. 
          
                    Interpret wiring diagrams 
          
                    Identify the following sensors if applicable to the engine: 
                      
                     a)      Primary speed / position sensor 
                     b)      Secondary speed / position sensor 
                     c)      Coolant temperature sensor 
                     d)      Coolant level sensor 
                     e)      Boost temperature sensor 
                     f)      Fuel temperature sensor 
                     g)      Oil pressure sensor 
                     h)      Fuel supply pressure sensor 
                     i)      Fuel rail pressure sensor 
                     j)      Crankshaft position sensor 
                     k)      Camshaft position sensor 
          
                    Test sensor wiring. 
          
                    Test sensors applicable to the engine 
          
                    Obtain the following : 
          
                         a)  common rail fuel pressure 
                         b)  boost pressure 
                         c)  fuel supply pressure. 
                         d)  intake air temperature 
                         e)  engine oil pressure 
          
      
                    Complete a condition report. 
              
             WHAT YOU WILL BE GIVEN 
              
                    A Common Rail Diesel engine. 
              
                    All the necessary tools and equipment. 
              
              
              
             Created : March 2015                                                                      First Published : March 2015 
             Revised : March 2015                                                                               Revision No: 001 
             Owner : Learnership Department                                                                              TRG 9 
                                                                                                                    Page 3 of 34 
                 Diesel Mechanic: CRD 
                  - Mining Qualifications Authority - All rights reserved. 
                  
             HOW WELL YOU MUST DO IT 
              
                    The following items if applicable must be tested as specified in the workshop manual: 
              
                     a)      Primary speed / position sensor 
                     b)      Secondary speed / position sensor 
                     c)      Coolant temperature sensor 
                     d)      Coolant level sensor 
                     e)      Boost temperature sensor 
                     f)      Fuel temperature sensor 
                     g)      Oil pressure sensor 
                     h)      Fuel supply pressure sensor 
                     i)      Fuel rail pressure sensor 
                     j)      Crankshaft position sensor 
                     k)      Camshaft position sensor. 
              
                    The wiring must be tested as specified in the workshop manual. 
                      
                    Record the following pressures correctly: 
                         a)  common rail fuel pressure 
                         b)  boost pressure 
                         c)  fuel supply pressure. 
                         d)  intake air temperature 
                         e)  engine oil pressure 
              
                    There must be no damage to the wiring and connectors 
                      
                    There must be no damage to the sensors 
                      
                    There must not be any damage to fasteners. 
              
                    All the fasteners must be tightened to specifications. 
              
             SOURCE REFERENCES 
              
                    A demonstration by a competent person e.g. your instructor. 
              
                    Workshop manual. 
              
                    Audio-visual aids, if available. 
              
              
              
              
              
              
              
             Created : March 2015                                                                      First Published : March 2015 
             Revised : March 2015                                                                               Revision No: 001 
             Owner : Learnership Department                                                                              TRG 9 
                                                                                                                    Page 4 of 34