Check Tire Pressure System - Pontiac 2004 Bonneville Owner's Manual

When to Check
Check your tires once a month or more.
Don't forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can't tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they're underinflated.
Remove the valve cap from the tire valve stem. Press
the tire gage firmly onto the valve to get a pressure
measurement. If the cold tire inflation pressure matches
the recommended pressure on the tire and loading
information label, no further adjustment is necessary. If
the inflation pressure is low, add air until you reach
the recommended amount. Be sure to put the valve caps
back on the valve stems. They help prevent leaks by
keeping out dirt and moisture.
If you overfill the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and
moisture.
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Check Tire Pressure System

The check tire pressure system can alert you to a large
change in the pressure of one tire. The system will not
alert you before you drive that a tire is low or flat. You
must begin driving before the system will work properly.
The CHECK TIRE PRESSURE message will appear on
the Driver Information Center (DIC) or the system
monitor TIRE PRESS light will come on if pressure
difference (low pressure) is detected in one tire.
The check tire pressure system may not alert you if:
•
More than one tire is low.
•
The vehicle is moving faster than 65 mph (105 km/h).
•
The system is not yet calibrated.
•
The compact spare tire is installed.
•
The tire treadwear is uneven.
•
Tire chains are being used.
•
The vehicle is being driven on a rough or frozen road.
If the anti-lock brake system warning light comes on,
the check tire pressure system may not be working
properly. See your dealer for service. Also, see
Anti-Lock Brake System Warning Light on page 3-44.