Equus 3040 - OBD2 ScanTool - Manual (Page 28)

Using the Scan Tool
CODE RETRIEVAL PROCEDURE
26 OBD2
6.
The Scan Tool will automatically start a
check of the vehicle’s computer to
determine which type of communication
protocol it is using. When the Scan Tool
identifies the computer’s communication
protocol, a communication link is
established. The protocol type used by
the vehicle’s computer is shown on the
display.
A PROTOCOL is a set of rules and procedures for regulating data
transmission between computers, and between testing equipment
and computers. As of this writing, five different types of protocols
(ISO 9141, Keyword 2000, J1850 PWM, J1850 VPW and CAN)
are in use by vehicle manufacturers. The Scan Tool automatically
identifies the protocol type and establishes a communication link
with the vehicle’s computer.
„ If the Scan Tool fails to link to the
vehicle’s computer a “Linking Failed”
message shows on the Scan Tool’s
display.
- Verify the connection at the DLC,
and verify the ignition is ON.
- Turn the ignition OFF, wait five
seconds, then turn back ON to
reset the computer.
- Ensure your vehicle is OBD2 compliant. See VEHICLES
COVERED on page 3 for vehicle compliance verification
information.
„ The Scan Tool will automatically re-
link to the vehicle’s computer every
15 seconds to refresh the data being
retrieved. When data is being
refreshed, the message “One
moment - AUTO-LINK is in progress”
is shown on the LCD display. This
action repeats as long as the Scan
Tool is communicating with the
vehicle’s computer.
7.
After approximately 4~5 seconds, the Scan Tool will retrieve and
display any Diagnostic Trouble Codes, Monitor Status and Freeze
Frame Data retrieved from the vehicle’s computer memory.
„ The Scan Tool will display a code
only if codes are present in the
vehicle’s computer memory. If no
codes are present, a “No DTC’s or
Freeze Frame data presently stored
in the vehicle’s computer” message
is displayed.
„ The Scan Tool is capable of retrieving and storing up to 32 codes in
memory, for immediate or later viewing.