Ford Windstar Owner's Manual page 321

How to Prepare Your Vehicle for
Inspection/Maintenance (I/M) Testing
In some localities it may become a legal requirement to pass an
Inspection/Maintenance (I/M) test of the On-Board Diagnostic
(OBD) II system. If the vehicle's powertrain system or its battery
has just been serviced, the OBD II system is reset to a not ready
for I/M testing condition. To prepare for I/M testing, the law
specifies that additional mixed city and highway driving is
required to complete the check of the OBD II system.
The driving modes required to reach the ready condition consist
of a minimum of 30 minutes of city and highway driving as
described below:
At least twenty minutes driving in stop and go, city type
traffic with at least four idle periods.
At least ten minutes of driving on an expressway or
highway.
Before completing the above driving modes, the engine must be
warmed up and at operating temperature. Once started, the
vehicle must not be turned off during these driving modes.
Lights
It is a good idea to check the operation of the following lights
frequently:
headlamps
tail lamps
brakelamps
hazard flasher
turn signals
license plate lamps
fog lamps
Maintenance and Care
321