User Manual

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coolant temperature (ECT), or vehicle speed sensor (VSS) etc. This
information will aid the technician by allowing the parameters to be
duplicated for diagnostic and repair purposes.
I/M Readiness
I/M Readiness function is used to check the operations of the Emission
System on OBD II compliant vehicles. It is an excellent function to use prior
to having a vehicle inspected for compliance to a state emission program.
NOTE
By clearing trouble codes you also clear the readiness status for the
individual emission system readiness tests. In order to reset these monitors,
the vehicle must be driven through a complete drive cycle with no trouble
codes in memory. Times for reset vary depending on vehicle.
Some latest vehicle models may support two types of I/M Readiness tests:
A. Since DTCs Cleared – indicates status of monitors since the DTCs are
erased.
B. This Drive Cycle – indicates status of monitors since the beginning of
the current drive cycle.
An I/M Readiness Status result of “NO” does not necessarily indicate that the
vehicle being tested will fail the state I/M inspection. For some states, one or
more such monitors may be allowed to be “Not Ready” to pass the emission
inspection.
 OK – indicates that a particular monitor being checked has completed
its diagnostic testing.
 INC – indicates that a particular monitor being checked has not
completed its diagnostic testing.
 N/A – the monitor is not supported on that vehicle.
O2 Monitor Test
OBD II regulations set by SAE require the relevant vehicle monitors and
tests on the oxygen (O2) sensors to identify problems related to fuel
efficiency and vehicle emissions. These tests are not on-demand tests and
they are done automatically when engine operating conditions are within