TPMS has been calibrated to use air in the tire. Use of 100 percent nitrogen may affect the accuracy of the system.
Each tire should be checked cold before riding and inflated to the inflation pressure recommended by Harley-Davidson in Specifications → Specifications → Specified Tires and shown on the VIN/tire inflation pressure label (included on vehicles in US/Canada).
Your vehicle has been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pressure lamp when one or more of your tires is significantly under-inflated. Accordingly, when the low tire pressure lamp illuminates, stop and check your tires as soon as possible, and inflate them to the proper pressure. Driving on a significantly under-inflated tire causes the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire tread life, and may affect the vehicle's handling and stopping ability. It is important to set the tire pressure properly. Failure to do so can result in a low pressure alert at higher ambient air temperatures. Recommended cold tire pressures are shown in Specifications → Specifications → Specified Tires.
If tire pressure is to be checked when the vehicle has been recently ridden and the tires are warm, refer to Specifications → Tire Data → Tire Pressure Adjustment to determine corrected pressures. If tire pressure is adjusted per Specifications → Tire Data → Tire Pressure Adjustment, readjust per cold tire recommendation at the earliest convenience.
TPMS is not a substitute for proper tire maintenance. It is the rider's responsibility to maintain correct tire pressure, even if under-inflation has not reached the level to trigger illumination of the TPMS low tire pressure lamp.
The vehicle has also been equipped with a TPMS malfunction indicator to indicate when the system is not operating properly. The TPMS malfunction indicator is combined with the low tire pressure lamp. When the system detects a malfunction, the low tire pressure lamp will flash for approximately one minute and then remain continuously illuminated. This sequence will continue upon subsequent vehicle start-ups as long as the malfunction exists. The security lamp will also turn on to indicate that a diagnostic trouble code exists. When the malfunction indicator is illuminated, the system may not be able to detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of reasons, including the installation of replacement tires or wheels on the vehicle that prevent the TPMS from functioning properly.
Always check the TPMS malfunction indicator after replacing one or more tires or wheels on your vehicle to en sure that the replacement tires and wheels allow the TPMS to continue to function properly.