HOLDEN GEN III V8, Service Training

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GEN III V8 ENGINE MANAGEMENT
F3: Miscellaneous Tests
In this test mode, the Tech 2 scan tool performs software override commands of the PCM, to assist in problem
isolation during diagnostics.
FO: Output Tests
FO: Fuel Pump: Fuel Pump Relay can be commanded on and off.
F1: A/C Clutch: A/C Compressor Clutch can be commanded on and off.
F2: Check Powertrain Lamp: Check Powertrain Lamp can be commanded on and off.
F3: High Fan: High Speed Cooling Fan operation can be commanded on and off.
F4: Canister Purge: Canister Purge can be commanded on (100%) and off (0%).
F1: IAC System
FO: RPM Control: Used to control engine RPM from 600 RPM to 1675 RPM.
F1: IAC Control: Used to control IAC steps from 0 to 120.
F2: IAC Reset: Used to reset IAC if the IAC is lost or if IAC has been replaced.
F3: Base Idle: Used to set the engine to base idle.
F2: Reset Cells
Resets all Long Term Fuel Trim values to 0%
F3: 02 Loop Status
With the engine running, Open or Closed Loop fuel control can be commanded.
F4: Function Tests
In this test mode, Tech 2 performs various automated tests to assist in problem isolation during trouble
shooting. To operate any of the Function Tests, simply select the appropriate test mode from the Function Test
application menu and follow the instructions as per TECH 2. When the Function Tests option is selected, the
following options will become available.
FO: IAC Circuit: This function automatically cycles the IAC valve in and out a calibrated number of steps and
cycle times, and compares the initial IAC valve steps to the end IAC valve steps to determine if the IAC valve
is controlling RPM properly and not losing steps.
Preconditions: Coolant temperature greater than 80°C, vehicle speed zero km/h, engine running at idle, air
conditioning turned off and engine cooling fans turned on.
F1: Power Balance: This function automatically turns off each injector sequentially for five seconds, while
the engine RPM is monitored. At the end of the test the minimum RPM for each cylinder is displayed.
Preconditions: Vehicle speed less than two km/h, engine running at idle, air conditioning turned off and the
engine cooling fans are turned on.
F3: Wiring Harness: During this function test TECH 2 monitors the following inputs: RPM, ECT, MAF, TPS,
Battery Voltage, Injector Voltage and VSS. If a change occurs in these circuits greater than the limits listed
below, the TECH 2 logs the failure and prompts the technician to check the appropriate circuit.
Preconditions: Engine running, vehicle speed less than two km/h.
F4: Fuel Injector Balance: This function is designed to check the fuel flow through each injector while the
engine is not running. A fuel pressure gauge has to be connected to the fuel rail. TECH 2 first turns on the
fuel pump. After pressure is established the fuel pump is turned off again and the injector is turned on for a
predetermined time. Pressure drop has to be read afterwards on the fuel gauge for each injector. This can be
performed only once per injector.
Preconditions: Vehicle speed less than 2 km/h, engine not running.
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