Konnwei KW830, Руководство пользователя

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2.7 OBD II Modes of Operation
Here is a basic introduction to the OBD II communication protocol
。
Mode byte : The first byte in the stream is the mode number
。
There are 10
modes for diagnostic requests
。
The first byte in the response data bytes is this
same number plus 64
。
For example
，
a mode 1 request would have the first
data byte =1
，
and the response would have the first data byte=65
。
Here is a
brief description of the modes :
Mode $01 – Identifies the Powertrain information and shows current
data available to the scan tool
。
This data includes: DTC set
，
status of
on-board tests
，
and vehicle data such as engine RPM
，
temperatures
，
ignition
advance
，
speed
，
air flow rates
，
and closed loop status for fuel system
。
Mode $02 – Displays Freeze Frame data
。
Same data as in mode 1
，
but it
was captured and stored when a malfunction occurred and a DTC was set
。
Some of the PIDs for mode one are not implemented in this mode
。
.
Mode $03 – Displays the type of powertrain or emission related DTCs
stored by a 5 digit code identifying the faults. There may be more than one
response message if there are more trouble codes than will fit in the data
bytes of the response message
，
or it there are more than one ECU computer
responding
。
Mode $04 – Used to clear DTCs and Freeze Frame data. This clears all
diagnostic trouble codes that may be set including freeze frame data and
readiness monitors
。
Mode $05 – Oxygen Sensor Test Results. This mode displays the oxygen
sensor monitor screen and the test results gathered about the oxygen sensor
。
There are ten numbers available for diagnostics:
1. $01 Rich-to-Lean O2 sensor threshold voltage.
2. $02 Lean-to-Rich O2 sensor threshold voltage.
3. $03 Low sensor voltage threshold for switch time measurement.
4. $04 High sensor voltage threshold for switch time measurement.
5. $05 Rich-to-Rich switch time in ms.
6. $06 Lean-to-Rich switch time in ms.
7. $07 Minimum voltage for test.
8. $08 Maximum voltage for test.
9. $09 Time between voltage transitions in ms.
7