OBD2 problem the car fault diagnostic conduct vehicle

4. attention to the meaning of the status information data
The control unit fault diagnostic data read out in a variety of ways, said the unit is not the same. For example, the throttle opening degree POLO car use "%" in the form of representation; automatic transmission multifunction switch, switch status information in 8-bit binary number; anti-theft electronic working conditions of the engine to four groups of "0" and "1" digital representation; throttle basic setting information with certain characters indicate its status. Understand the meaning of these expressions and data information, contribute to a more comprehensive understanding of the working status of the control unit and a number of sensors, information elements to perform.
Fault 5: an annual output of 2004 Santana 2000 GSi car, will start immediately after flameout, seemingly anti-theft system lockup, but security lights after the ignition is switched on self-test is normal. Fault diagnostic use query engine control system, the "engine control unit locked" fault logging, anti-theft system control unit without any fault records, anti-theft system can not see any problems. Then use the scan tool to read the work of anti-theft device status information, the status information group found four anti-theft system control unit, the engine control unit determines the state is "0", and the correct value of "1" does not match, the engine control unit and suspected alarm control unit between a burglar alarm or confirmation of the line control unit has a problem. Multimeter check the relevant line is normal, then replace the alarm control unit (Fig. 6) and to match, failure to exclude.


 Figure 6
In addition to these four essentials use, fault detection diagnostic service there are a few things can be brought in to play, to make it function to maximize the application, the key is how to professional users with rich theoretical system maintenance practice closely integrated, so that the information provided to the user can be fully utilized.
Tool:
Foxwell NT644
Foxwell NT300
Foxwell BT705
FoxwelL NT500
Foxwell NT301