Chevrolet TrailBlazer, Service Manual

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Battery Cables
WARNING
To avoid personal injury and/or vehicle damage, refer to the service precautions at the
beginning of this section.
Disconnecting The Cables
Before disconnecting the cable(s), first turn the ignition to the OFF position. This will
prevent a draw on the battery which could cause arcing (electricity trying to ground itself to
the body of a vehicle, just like a spark plug jumping the gap) and, of course, damaging
some components such as the alternator diodes.
Always disconnect the negative (
–) battery cable first. This will prevent accidentally
grounding the positive (+) terminal to the body of the vehicle when disconnecting it,
thereby preventing damage to the above mentioned components.
When the battery cable(s) are reconnected (negative cable last), be sure to check that the
lights, windshield wipers and other electrically operated safety components are all working
correctly. If the vehicle contains an Electronically Tuned Ra
dio (ETR), don’t forget to also
reset the radio stations and clock.
Air Bag (Supplemental Restraint System)
General Information
The SRS is a safety device which, when used with the seat belt, is designed to help
protect the driver and front passenger in a frontal impact exceeding a certain set speed
limit. The system consists of the SRS unit, including safing sensor and impact sensor, the
cable reel, the driver's airbag, the front passenger's airbag, side airbags, side curtain
airbags, seat belt tensioners, front impact sensors, side impact sensors and roll rate
sensor. Since the driver's and front passenger's airbags use the same sensors, both
normally inflate at the same time. However, it is possible for only one airbag to inflate. This
can occur when the severity of a collision is at the margin, or threshold, that determines
whether or not the airbags will deploy. In such cases, the seat belt will provide sufficient
protection, and the supplemental protection offered by the airbag would be minimal.
Service Precautions
Use replacement parts which are manufactured to the same standards and quality
as the original parts. Do not install used SRS parts. Use only new parts when
making SRS repairs.
Carefully inspect any SRS part before you install it.
Do not install any part that shows signs of being dropped or improperly handled,
such as dents, cracks or deformation.
Before removing any SRS parts (including disconnection of connectors), always
disconnect the SRS connector.
Use only a digital multimeter to check the system. Ensure that the multimeter
output is 10 mA (0.01 A) or less when switched to the lowest value in the