The OBD-II system is designed to check the emission control system
during normal driving. A complete check may take several days. If the
vehicle is not ready for I/M testing, the following driving cycle consisting
of mixed city and highway driving may be performed:
15 minutes of steady driving on an expressway/highway followed by 20
minutes of stop-and-go driving with at least four 30 second 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. If
the vehicle is still not ready for I/M testing, the above driving cycle will
have to be repeated.
On board diagnostics (OBD-II)
Your vehicle is equipped with a computer that monitors the engine’s
emission control system. This system is commonly known as the On Board
Diagnostics System (OBD-II). The OBD-II system protects the environment
by ensuring that your vehicle continues to meet government emission
standards. The OBD-II system also assists your authorized dealer in
properly servicing your vehicle. When the
indicator illuminates, the
OBD-II system has detected a malfunction. Temporary malfunctions may
cause the
indicator to illuminate. Examples are:
1. The vehicle has run out of fuel—the engine may misfire or run poorly.
2. Poor fuel quality or water in the fuel—the engine may misfire or run
poorly.
3. The fuel cap may not have been securely tightened. SeeFuel filler
capin this chapter.
4. Driving through deep water – the electrical system may be wet.
These temporary malfunctions can be corrected by filling the fuel tank
with good quality fuel, properly tightening the fuel cap or letting the
electrical system dry out. After three driving cycles without these or any
other temporary malfunctions present, the
indicator should stay off
the next time the engine is started. A driving cycle consists of a cold
engine startup followed by mixed city/highway driving. No additional
vehicle service is required.
If theindicator remains on, have your vehicle serviced at the first
available opportunity. Although some malfunctions detected by the OBD-II
may not have symptoms that are apparent, continued driving with the
indicator on can result in increased emissions, lower fuel economy, reduced
engine and transmission smoothness, and lead to more costly repairs.
2007 Motorhome(mot)
Supplement
USA(fus)
Maintenance and Specifications
107
