46
OBD-II/EOBD Operations
OBD Direct
MIL Status
This item is used to check the current condition of the Malfunction Indicator (MIL). Additional
information, such as which ECM commanded the MIL on and the distance driven while the MIL is
on (if supported), can also be displayed. It is also possible to save the MIL Status report.
($01) Display Current Data
Use this item to display the current emission related data from the selected electronic control
module (ECM) of the vehicle. Displayed data includes analog inputs and outputs, digital inputs and
outputs, and system status information broadcast on the vehicle data stream.
($02) Display Freeze Frame Data
This item is used to display freeze fame data for any stored emission related diagnostic trouble
codes (DTCs). In most cases the stored frame is the last DTC that occurred. Certain DTCs, those
that have a greater impact on vehicle emission, have a higher priority. In these cases, the highest
priority DTC is the one for which the freeze frame records are retained in memory.
Freeze frame data includes a snapshot of critical parameter values at the time the DTC set.
($03) Display Trouble Codes
This is used to display any stored emission related DTCs reported by the various ECMs.
($04) Clear Emissions Related Data
This item is used to clear all emission related diagnostic data such as, DTCs, freeze frame data,
and test results from the memory of the selected ECM.
($05, 06, 07) Display Test param./Results
This selection opens a submenu of test parameters and test results from various sensors, such as
the oxygen sensor (O2S), monitor test results, and a record of DTCs detected during the last drive
cycle.
The Test Parameters and Test Results menu includes:
•
Oxygen Sensor Monitoring ($05)
•
Specific Monitored Systems ($06)
•
DTCs Detected During Last Drive ($07)
($08) Request Control of On-board System
This service enables bidirectional control of the ECM, that is the scan tool transmits control
commands to operate the vehicle system. This function is useful in determining how well the ECM
responds to a command.