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6 LED and AUDIO
6.1 LED Interpretation
1)
GREEN LED — Indicates that engine systems are “OK” and operating normally (the
number of Monitors supported by the vehicle which have run and performed their
self-diagnostic testing is in the allowed limit. MIL is off). There are no stored and pending
DTCs. The vehicle is ready for an Emissions Test, and there is a good possibility that it can
be certified.
2)
YELLOW LED -- With MEL off, there may be three possible conditions to cause the
yellow LED to light.
A.If a”Stored” Diagnostic Trouble Code is causing the Yellow LED to light, it is ttill
possible that the vehicle will be allowed to be tested for emissions and certified.
B. If a “Pending
”
Diagnostic Trouble Code is causing the Yellow LED to light, it is
still possible that the vehicle will be allowed to be tested for emissions and certified.
C. If the illumination of the Yellow LED is being caused by monitors that have not
completed their diagnostic testing, then the issue of the vehicle being ready for an
Emissions Test depends on the emissions regulations and laws of your local area.
NOTE: From the code retrieval procedure, determine the status of each monitor, take this
information to an emissions professional to determine (based on your test results) if your
vehicle is ready for an Emissions Test.
3)
RED LED — Indicates there is a problem with one or more of the vehicle’s system. A
vehicle displaying a red LED is definitely not ready for an Emissions Test. TTie red LED is
also vehdcle*s instrument panel will light steady. The problem that is causing the red LED
to light must be repaired before an Emissions Test can be performed . It is also suggested
that the vehicle be inspected/rq^aired before driving the vehicle further.
A.
Repair the vehicle yourself. If you are going to perform the repairs yourself,
proceed by reading the veliicle service manual and following all its procedures and
recommendations.
B.
Take the vehicle to a professional to have it serviced The problem(s) causing the
red LED to light must be repaired before the vehicle is ready for is ready for an Emissions
Test.
6.2 Audio Tone Interpretation
The audio tone is configured according to tiie
I/M
readiness Status. This function is
invaluable when performing diagnostics and driving at the same time, or working in bright
areas where LED illumination alone is not sufficient.
Different audio tone with different LED light indicates different 1/M Readiness Status.