Voltage - Isuzu 2000 Trooper Workshop Manual

Diagnostic Trouble Code (DTC) P0462 Fuel Level Sensor Circuit–Low Voltage
Circuit Description
The fuel level sensor is an important input to powertrain
control module (PCM) for the enhanced evaporative
system diagnostic. Fuel level information is needed for
the PCM to know the volume of fuel in the tank. The fuel
level affects the rate of change in air pressure in the
evaporative system.
evaporative system diagnostic sub-tests are dependent
upon correct fuel level information. The diagnostic will not
run when the tank is greater than 85%, or less than 15%
full. Fuel level DTCs should be diagnosed before other
evaporative system DTCs because they can cause other
DTCs to be set.
The sending unit is a float in the fuel tank which moves a
wiper arm across a variable resistor. Low fuel level
causes high resistance in the sending unit, and this is
recognized by the PCM because the circuit operates at a
corresponding low voltage.
continuously open or has a high resistance connection,
DTC P0462 is set.
Conditions for Setting the DTC
D Fuel tank level "slosh test" is completed.
D Fuel tank level "main test" is completed.
D Fuel tank level data is valid.
D Fuel tank level signal is less than a specified value.
D There are 100 test failures within a 200-test sample.
TROOPER 6VE1 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Several of the enhanced
When the circuit is
Action Taken When the DTC Sets
D The PCM will not turn the malfunction indicator lamp
(MIL) "ON."
D The PCM will store conditions which were present
when the DTC was set as Failure Records only. This
information will not be stored as Freeze Frame data.
Conditions for Clearing the DTC
D The PCM will turn the MIL "OFF" after three
consecutive trips without a fault condition present. A
history DTC will be cleared if no fault conditions have
been detected for 40 warm-up cycles (engine coolant
temperature has risen 4°C (40°F) from the start-up
ECT, and ECT exceeds 71°C (160°F) during that
same ignition cycle).
D DTC P0462 can be cleared by using the scan tool
"Clear Info" function or by disconnecting the PCM
battery feed.
Diagnostic Aids
D Damaged harness–Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
fuel level display on the scan tool while moving
connectors and wiring harnesses related to the sensor.
A change in the display will indicate the location of the
fault.
6E–347
060RY00163