Chevrolet Trailblazer Service Manual page 33

Timing belt maintenance is extremely important. Many models utilize an
interference-type, non-freewheeling engine. If the timing belt breaks, the valves in
the cylinder head may strike the pistons causing potentially serious (also time-
consuming and expensive) engine damage. Refer to the maintenance interval
charts in the front of this manual for the recommended replacement interval for the
timing belt, and to the timing belt section for belt replacement and inspection.
All new vehicles are now equipped with an air bag system. The system must be
disabled before performing service on or around system components, steering
column, instrument panel components, wiring and sensors. Failure to follow safety
and disabling procedures could result in accidental air bag deployment, possible
personal injury and unnecessary system repairs.
Always wear safety goggles when working with, or around, the air bag system.
When carrying a non-deployed air bag, be sure the bag and trim cover are pointed
away from your body. When placing a non-deployed air bag on a work surface,
always face the bag and trim cover upward, away from the surface. This will reduce
the motion of the module if it is accidentally deployed. Refer to the additional air
bag system precautions later in this section.
Disconnecting the negative battery cable on some vehicles may interfere with the
functions of the on-board computer system(s) and may require the computer to
undergo a relearning process once the negative battery cable is reconnected.
Batteries contain corrosive acid. Batteries supply current high enough to cause
burns. Batteries produce explosive gases. When working on batteries always wear
eye protection. Never allow battery acid to contact the skin or eyes. Do not allow
sparks or flames near the battery.
NOTE: Disconnecting the negative battery cable on some vehicles may interfere with the
functions of the on board computer system. The computer may undergo a relearning
process once the negative battery cable is reconnected.