Isuzu 4HL1 Workshop Manual page 86

1A-84 Engine Control System
VIM Data
Tech 2 Data
Item
Display
1/31 System Voltage
2/31 Vehicle Speed
3/31 Barometric
Pressure Sensor
4/31 Barometric
Pressure
5/31 PTO Accelerator
Sensor
6/31 PTO Accelerator
Opening
7/31 Ignition Switch
8/31 Idle Up Volume
Units
displayed
V This parameter refers to the
power supply voltage applied to
the VIM from the battery.
km/h This parameter refers to the
value calculated by the VIM using
the signals from the VS sensor.
V This parameter refers to the
signal voltage input to the VIM
from the barometric pressure
sensor. (Higher barometric
pressure provides higher
voltage.)
kPa This parameter refers to the
value calculated by the VIM using
the signals from the barometric
pressure sensor.
V This parameter refers to the
voltage signal input to the VIM
from the PTO accelerator sensor.
(Larger PTO accelerator position
provides higher voltage.)
% This parameter refers to the
value calculated by the VIM using
the signals from the PTO
accelerator sensor.
ON/OFF This parameter refers to the
status of the signals input from
the key switch to the VIM. It
appears on the display after the
key switch is moved to the
position "ON" or "ST".
V This parameter refers to the
signal voltage input to the ECM
from the idle up volume. (Higher
idle speed provides higher
voltage.)
Description How to use parameters
When the display substantially
deviates from the actual battery
voltage, a voltage drop may
occur due to accessories
installed to the circuit. If it
deviates from the specified level,
the circuit, connector, connector
mating, or VIM may be faulty.
When the display differs from the
speedometer reading or is
unchanged, major cause may lie
in VS sensor, circuit, VIM, or
ECM.
The barometric pressure sensor
is a proper criterion for various
control configurations (e.g.,
startup, cold, or post-warmup
condition). This parameter may
be used as one of DTC detection
conditions.
When the display deviates from
the specified level, the sensor,
circuit, or ECM may be faulty.
When the display deviates from
the specified level as the PTO
accelerator position is changed,
the sensor, circuit, VIM, or ECM
may be faulty.
When the display deviates from
the specified level as the PTO
accelerator position is changed,
the sensor, circuit, VIM, or ECM
may be faulty.
When the display is fixed, the
switch, circuit, VIM,or ECM may
be faulty.
When the display is improper, the
idle up volume, circuit, VIM, or
ECM may be faulty.