How to use Fcar F3-D Heavy Duty Scanner to Read DTC (Diagnostic Trouble Codes)
Time: 2017-05-10 Reads: 3221 Edit: Admin
Take F3-D Heavy duty scanner as an example, to diagnose and remove fault, you need first connect F3-D truck diagnostic scanner to diagnostic socket of vehicle, as shown in Pic.4-37. It has special functions as follow, such as engine off-cylinder running, test injection solenoid valve response time, calibrate and replace injector, take rapid sample of engine data, user can limitedly alter ECU program etc. under engine manufacturer restricted working condition or characteristic parameter.
Maintenance technician can use Fcar car diagnostic tools to enter ECU memory, monitor sensor output, read DTC, And also selectively program options that already exists in system.
Different engine manufacturer, the fault code coding system and interpreter program are different. Such as CAT, Cummins, DETROIT DIESEL, MACK and VOLVO, the fault that each company engine fault code referred to is different. SAE CGATS and engine manufacturer worked together to formulate a standard system about electronic code and its implication, to encourage the whole industry to adopt serial data communication system in engine. SAE has drawn up SAE-J series reference standard, and now has been applied.
●SAE J1587 this standard enable to have” talk “(information exchange)with diagnostic tool,trip recorder and vehicle information management system,electronic instrument display system and satellite system. In other words, J1587 and J1708 data communication system can provide data of sensor and engine to other control modules of vehicle.
●SAE J1922 and J1939 these two standards enable ECU to communicate with other electronically controlled system such as ABS, drive slip control system(traction control system),to provide data for other electronically controlled systems. Vehicle communication line connects J1922 and J1939 data control interfaces of ECU to other electronically controlled systems, J1939 data transmission system adopts CAN communication protocol.
●SAE J1924 is a standard about microcomputer software compatibility, which enables computer to connect to ECU interface, and explain data signal from ECU, software installed as terminate and stay resident (TSR）.
When use Fcar auto scanner as shown in Pic. 4-36 to decode DTC saved in ECU, the DTC and its definition can be displayed. Referring to DTC and its definition that the scanner displayed, maintenance Technician gradually locate where the fault is, and find the real cause to fault.
To read DTC, the diagnostic connector must be found firstly and then connect with Auto Scan tools(as shown in Pic 4-36).As engines and automakers are different, diagnostic sockets are normally different. Considering diagnostic socket used by some automakers are not standard connectors, the diesel version of Fcar Auto Scan tools are now equipped with diagnostic connectors of common vehicle models, but there are still part of models assembled with different diagnostic connectors because of different requests of manufacturer. Regarding this aspect, Fcar Auto Scan tools specially equipped with universal jumper box and jumper for those without suitable diagnostic connector.
Pic. 4-38 Universal jumper box and need jumper combination-D Heavy Duty Scanner to Read DTC (Diagnostic Trouble Codes)