If you take your vehicle for a state
emissions test shortly after the
battery has been disconnected or
gone dead, it may not pass the test.
This is because of certain ‘‘readiness
codes’’ that must be set in the on-
board diagnostics for the emissions
systems. These codes are erased
when the battery is disconnected,
and set again only after several days
of driving under a variety of
conditions.
If the testing facility determines that
the readiness codes are not set, you
will be requested to return at a later
date to complete the test. If you must
get the vehicle re-tested within the
next two or three days, you can
condition the vehicle for retesting by
doing the following.
Make sure the gas tank is nearly,
but not completely, full (around
3/4).
Make sure the vehicle has been
parked with the engine off for 8
hours or more.
Make sure the ambient
temperature is between 20° and
95°F.
Without touching the accelerator
pedal, start the engine, and let it
idle for 20 seconds.
Keep the vehicle in Neutral.
Increase the engine speed to 2,000
rpm, and hold it there until the
temperature gauge rises to at least
1/4 of the scale (about 3 minutes).
State Emissions Testing
Testing of Readiness Codes
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