battery is disconnected or a new battery is installed,
the engine must relearn its idle and fuel trim
strategy for optimum driveability and performance.
To begin this process:
1. With the vehicle at a complete stop, set the
parking brake.
2. Put the gearshift in P (Park) (automatic
transmission) or the neutral position (manual
transmission), turn off all accessories and start the
engine.
3. Run the engine until it reaches normal operating
temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for
at least one minute.
6. Drive the vehicle to complete the relearning
process.
•The vehicle may need to be driven 16 km
(10 miles) or more to relearn the idle and fuel
trim strategy.
•If you do not allow the engine to relearn its
idle trim, the idle quality of your vehicle may
be adversely affected until the idle trim is
eventually relearned.
When the battery is disconnected or a new battery
installed, the transmission must relearn its adaptive
strategy. As a result of this, the transmission may
shift firmly. This operation is considered normal and
will not affect function or durability of the
transmission. Over time the adaptive learning
process will fully update transmission operation to
its optimum shift feel.
If the battery has been disconnected or a new
battery has been installed, the clock and the preset
radio stations must be reset once the battery is
reconnected.
2004 Mustang(mus)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
173
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
MERCONAT F.
If your vehicle is
equipped with the
OHV V6 engine,
check the power
steering fluid level with
the engine at normal
operating temperature.
1. Start the engine and
let it run until it
reaches normal
operating temperature
(the engine coolant
temperature gauge
indicator will be near
the center of the
normal area between H
and C).
FILL
HOT
2004 Mustang(mus)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
194
