2004 Ford Mustang Owner Guide 3rd Printing - Page 197

Maintenance and Specifications Readiness for Inspection/Maintenance (I/M) testing In some localities, it may be a legal requirement to pass an I/M test of the on-board diagnostics system. If your Check engine/Service engine soon light is on, refer to the description in the Warning lights and chimes section of the Instrument Cluster chapter. Your vehicle may not pass the I/M test with the Check engine/Service engine soon light on. If the vehicle's powertrain system or its battery has just been serviced, the on-board diagnostics system is reset to a "not ready for I/M test" condition. To ready the on-board diagnostics system for I/M testing, a minimum of 30 minutes of city and highway driving is necessary as described below: • First, at least 10 minutes of driving on an expressway or highway. • Next, at least 20 minutes driving in stop-and-go, city-type traffic with at least four idle periods. Allow the vehicle to sit for at least eight hours without starting the engine. Then, start the engine and complete the above driving cycle. The engine must warm up to its normal operating temperature. Once started, do not turn off the engine until the above driving cycle is complete. CHECKING AND ADDING POWER STEERING FLUID Check the power steering fluid. Refer to the scheduled maintenance guide for the service interval schedules. If adding fluid is necessary, use only MERCON௡ ATF. 197 2004 04- Mustang (mus) Owners Guide (post-2002-fmt) USA English (fus)