User manual

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Operations Select Protocol
Figure 7-10 Sample mode definition
7.5 Select Protocol
This main menu option allows you to select which communication protocol the MICROSCAN unit
uses to retrieve data from the ECM. For most instances, the MICROSCAN software automatically
determines which protocol to use based on the signals received from the ECM.
When the MICROSCAN is connected to the DLC it transmits an inquiry signal and looks for
responses from the vehicle ECMs to determine the protocol. In certain cases a non-emissions
ECM may respond first on a different communication line than what is used for the
emissions-related ECMs. When this happens, the MICROSCAN cannot retrieve DTC and other
pertinent data because it is not receiving the correct data. The Select Protocol option allows you
to choose the correct communications link in the rare instances when this happens. Selecting
opens a sub-menu.
Figure 7-11
Sample select protocol menu
Scroll and press Y to select from the menu.
GLOBAL OBD-2/EOBD HELP
Service MODE $01:
Current Powertrain Data
System Readiness Test
Display:
MIL or malfunction control;
SELECT PROTOCOL
ISO 15765-4 (CAN)
ISO 9141-2
ISO 14230-4 (KWP2000)
SAE J1850 (PWM)
SAE J1850 (VPW)