catalyst code...

Found this:

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 onboard
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 retested 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 Park
(automatic transmission) or
Neutral (manual transmission).
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 3minutes).

Select a nearby lightly traveled
major highway where you can
maintain a speed of 50 to 60 mph
(80 to 97 km/h) for at least 20
minutes.
Drive on the highway in D (A/T)
or 5th/6th (M/T). Do not use the
cruise control. When traffic allows,
drive for 90 seconds without
moving the accelerator pedal.
(Vehicle speed may vary slightly;
this is okay.) If you cannot do this
for a continuous 90 seconds
because of traffic conditions, drive
for at least 30 seconds, then repeat
it two more times (for a total of 90
seconds).

Then drive in city/suburban
traffic for at least 10 minutes.
When traffic conditions allow, let
the vehicle coast for several
seconds without using the
accelerator pedal or the brake pedal.

If the testing facility determines the
readiness codes are still not set, see
your dealer.