K Tahoe 4WD V8-4.8L VIN V (2000)
circuit board.
Electronic components used in the control systems are often designed in order to carry very low voltage. Electronic components are susceptible to
damage caused by electrostatic discharge. Less than 100 volts of static electricity can cause damage to some electronic components. There are several
ways for a person to become statically charged. The most common methods of charging are by friction and by induction. An example of charging by
friction is a person sliding across a car seat. Charging by induction occurs when a person with well insulated shoes stands near a highly charged object
and momentarily touches ground. Charges of the same polarity are drained off, leaving the person highly charged with the opposite polarity. Static
charges can cause damage. Therefore, it is important to use care when handling and testing electronic components.
Engine Controls Information
The driveability and emissions information describes the function and operation of the Powertrain Control Module (PCM).
The engine controls Information contains the following:
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Component locations
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Wiring diagrams
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PCM terminal end view and terminal definitions
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powertrain On Board Diagnostic (OBD) System Check
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Diagnostic Trouble Code (DTC) tables
The Component System includes the following items:
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Component and circuit description
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On-vehicle service for each subsystem
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Functional checks and diagnostic tables
The DTCs also contain diagnostic support information containing circuit diagrams, circuit or system information, and helpful diagnostic information.
Maintenance Schedule
Refer to the General Motors Maintenance Schedule of the appropriate service category for the maintenance that the owner or technician should perform
in order to retain emission control performance.
Visual and Physical Underhood Inspection
Perform a careful visual and physical underhood inspection when performing any diagnostic procedure or diagnosing the cause of an emission test
failure. This can often lead to repairing a problem without further steps. Use the following guidelines when performing a visual and physical inspection:
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Inspect all vacuum hoses for the following conditions:
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Correct routing
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Pinches
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Cuts
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Disconnects
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Inspect all wires in the engine compartment for the following conditions:
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Proper connections
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Burned or chafed spots
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Pinched wires
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Contact with sharp edges
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Contact with hot exhaust manifolds
This visual and physical inspection is very important.
Perform the inspection carefully and thoroughly.
Basic Knowledge Of Tools Required
IMPORTANT: Lack of basic knowledge of this powertrain when performing diagnostic procedures could result in incorrect diagnosis or damage to
powertrain components. Do not attempt to diagnose a powertrain problem without this basic knowledge.
A basic understanding of hand tools is necessary in order to effectively use this information.
System Status and Drive Cycle For Inspection/Maintenance
The System Status selection is included in the scan tool System Info menu.
Several states require that the I/M (OBD II system) pass on-board tests for the major diagnostics prior to having a vehicle emission inspection. This is
also a requirement to renew license plates in some areas. Using a scan tool, the technician can observe the System Status, complete or not complete, in
order to verify that the vehicle meets the criteria to comply with local area requirements. Using the System Status display, any of the following systems
or combination of systems may be monitored for I/M Readiness:
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The catalyst
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The EVAP system
