HOLDEN GEN III V8, Обучение по обслуживанию

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GEN III V8 ENGINE MANAGEMENT
DIAGNOSIS
The Rowel-train Management Section of the Service Manual is where to start all dnveability and emissions
diagnosis Once you have read and understood the General Information Section which contains reference
material wiring diagrams, PCM terminal end views and normal voltages, and component locations (Remember,
this information is for reference, do not start diagnosis using these pages) Always start diagnosis on the page
titled On-Board Diagnostic System Check This check first verifies that the diagnostic circuits are operating
properly and then sends you to the correct service manual page for diagnosis
If the initial steps in the On-Board Diagnostic System Check reveal a problem, or if the engine does not start,
you will be using one or more A charts for diagnosis Again, the On-Board Diagnostic System Check will send
you to the correct chart These charts follow the On-Board Diagnostic System check and diagnose both
fundamental PCM diagnostics and problems that prevent the engine from starting
If the On-Board Diagnostic System Check shows that Diagnostic Trouble Codes (DTC) have been stored,
proceed to the appropriate Diagnostic Trouble Code diagnosis pages If more than one diagnostic trouble code
has been stored, always start diagnosis with the lowest diagnostic trouble code number and work upward
Diagnostic trouble code diagnosis pages start immediately after the A chart pages
Diagnostic Precautions
The following requirements must be observed when working on vehicles:
1. Before removing any PCM system component, disconnect the battery earth lead
2. Never start the engine without the battery being solidly connected
3. Never separate the battery from the on board electrical system while the engine is running
4. When charging the battery, disconnect it from the vehicle's electrical system
5. Never subject the PCM to temperatures above 80 degrees C i e paint oven Always remove control unit first
if this temperature is to be exceeded
6. Ensure that all cable harness plugs are connected solidly and that battery terminals are thoroughly clean
7. The PCM harness connectors are designed to fit in only one way, there are indexing tabs and slots on both
halves of the connector Forcing the connector into place is not necessary if it is being installed with the
proper orientation Failure to take care to match the indexing tabs and slots to ensure the connector is being
installed correctly can cause damage to the connector, the module, or other vehicle components or
systems
8. Never connect or disconnect cable harness plug at the PCM when the ignition is switched on
9. Before attempting any electric arc welding on the vehicle, disconnect the battery leads and the PCM
connectors
10. When steam cleaning engines, do not direct the steam cleaning nozzle at PCM system components If this
happens, corrosion of the terminals can take place
1 1 . Use only the test equipment specified in the diagnostic charts, since other test equipment may either give
incorrect results or damage good components
12. All voltage measurements using a voltmeter must use a digital voltmeter with an internal impedance rating
of at least 1 0 million ohms per volt (10 meg ohms)
13. When a test light is specified, a low-power test light must be used Do not use a high - wattage test light
While a particular brand of test light is not suggested, a simple test on any test light will ensure it to be OK
for PCM circuit testing Connect an accurate ammeter (such as the high-impedance digital multimeter) in
series with the test light being tested, and power the test light-ammeter circuit with the vehicle battery
If the ammeter indicates tess than 3/10 amp current flow (0 3 A or 300 mA), the test light is OK to use
If the ammeter indicates more than 3/10 amp current flow (0 3 A or 300 mA), the test light is NOT OK to
use
Blocking Drive Wheels
The vehicle drive wheels should always be blocked and parking brake firmly set while checking the system
Visual/Physical Inspection
A careful visual and physical inspection must be performed as part of any diagnostic procedure or in
finding the cause of an emissions test failure. This can often lead to fixing a problem without further steps
Inspect all electrical wires for correct routing, pinches, cuts, or disconnections Be sure to inspect wires that are
difficult to see beneath the air cleaner, compressor, generator, etc Inspect all the wires in the engine
compartment for proper connections, burned or chafed spots, pinched wires, or contact with sharp edges or hot
exhaust manifolds This visual/physical inspection is very important It must be done carefully and thoroughly
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