Isuzu 2008MY N Series Workshop Manual page 48

Idle Up Sensor
This parameter displays the voltage signal sent to the
ECM from the idle up sensor. Idle up sensor is a range
of value indicating a low voltage when the idle up
sensor rotates in a counterclockwise direction to a high
voltage when the idle up sensor rotates in a clockwise
direction.
Fuel Compensation Cyl. 1 to 4
This parameter displays the adjustment of fuel volume
for each cylinder at low engine speed area as
calculated by the ECM. The scan tool will display a
negative value if the fuel volume is lowered. The scan
tool will display a positive value if the fuel volume is
increased. If there is a cylinder that is excessively high
or low value, it may indicate faulty fuel injector, weak or
slightly seized cylinder or an incorrectly programmed
fuel injector ID code.
Fuel Supply Pump Status
This parameter displays the learning state of the fuel
supply pump. Not Learned indicates initialized state
that is replaced to a new ECM or adjustment value is
reset. After engine is warm upped, leaning will start at
idle speed. Learned indicates learning process is
completed state.
Rail Pressure Feedback Mode
This parameter displays the state of the fuel rail
pressure feedback to the ECM. Wait Mode indicates
the ignition switch is turned ON position. Feedback
Mode indicates the engine is run. Shutoff Mode
indicates the ignition switch is turned OFF position.
Engine Mode
This parameter displays the state of engine. Ignition On
indicates the ignition switch is turned ON position.
Cranking indicates the engine is during crank. Running
indicates the engine is run. Off indicates the ignition
switch is tuned OFF position.
Engine Runtime
This parameter displays the time elapsed since the
engine start. The scan tool will display the time in
hours, minutes and seconds.
Vehicle Speed
This parameter indicates the vehicle speed calculated
by the ECM using the signal from the vehicle speed
sensor (VSS). The scan tool will display a low value at
lower vehicle speeds, and a high value at higher
vehicle speeds.
Starter Switch
This parameter displays the input status of the starter
switch to the ECM. When the ignition switch is turned at
START position, the scan tool displays On.
Ignition Switch
This parameter displays the input status of the ignition
switch to the ECM. When the ignition switch is turned
ON position, the scan tool displays On.
Engine Control System (4HK1)
Ignition Voltage
This parameter displays the ignition voltage measured
at the ignition feed circuit of the ECM. Voltage is
applied to the ECM when the ignition switch is ON
position.
Battery Voltage
This parameter displays the battery voltage measured
at the ECM main relay switched voltage feed circuit of
the ECM. Voltage is applied to the ECM when the ECM
main relay is energized.
Clutch Pedal Switch
This parameter displays the input state of the clutch
pedal switch to the ECM. When the clutch pedal is
depressed, scan tool displays Applied. If the Smoother
is installed, gearshift clutch input state from the TCM is
displayed.
Neutral Switch
This parameter displays the input state of the neutral
switch to the ECM. When the transmission gear is Park
or Neutral, the scan tool displays Neutral.
Park Brake Switch
This parameter displays the input state of the park
brake switch to the ECM. When the park brake lever is
pulled, scan tool displays Applied.
Exhaust Brake Switch
This parameter displays the input state of the exhaust
brake switch to the ECM. On indicates the exhaust
brake switch is closed and allows energizing the
exhaust brake solenoid valve and intake throttle
depending upon driving condition. Off indicates the
exhaust brake switch is open and exhaust brake will
not engage.
Exhaust Brake Valve Command
This parameter displays the commanded state of the
exhaust brake solenoid valve control circuit. On
indicates the exhaust brake solenoid valve is being
grounded by the ECM, allowing vacuum pressure to
the exhaust brake valve.
Exhaust Brake Cut Request from ABS Module
This parameter displays the state of the exhaust brake
cut request to the ECM from the electric hydraulic
control unit (EHCU). Active indicates the EHCU is
commanding to release the exhaust brake.
Exhaust Brake Cut Request from TCM
This parameter displays the state of the exhaust brake
cut request to the ECM from the transmission control
module (TCM). Active
commanding to release the exhaust brake.
1A-45
indicates the TCM is