Isuzu 1999 RODEO Workshop Manual page 1579

6E2–336
RODEO 6VD1 3.2L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0452 Fuel Tank Pressure Sensor Low Voltage
Circuit Description
The powertrain control module (PCM) monitors fuel tank
pressure sensor of the Enhanced Evapo system. When
the tank pressure output indicates low voltage, PCM will
set DTC P0452.
Conditions for Setting the DTC
f Ignition voltage is between 0.3 and 4.7 volts.
f Tank sensor output is less than 0.2 volts for 12.5 sec.
f 100 test failures within a 200 tests.
Action Taken When the DTC Sets
f The PCM will illuminate the malfunction indicator lamp
(MIL) as soon as failure detected.
f The PCM will store conditions which were present
when the DTC was set as Freeze Frame and in Failure
Records data.
Conditions for Clearing the MIL/DTC
f The PCM will turn the MIL "OFF" on the third
consecutive trip cycle during which the diagnostic has
been run and the fault condition is no longer present.
f A history DTC P0402 will clear after 40 consecutive
warm-up cycles have occurred without a fault.
f DTC P0404 can be cleared by using the Tech 2 "Clear
Info" function or by disconnecting the PCM battery
feed.
Diagnostic Aids
Check for the following conditions:
f Open circuit of 5 volt reference line – Inspect wiring
harness from PCM to the sensor. The PCM turns
P0452, and P0107 at the same time.
f Open circuit or short circuit to ground line – Inspect
wiring harness from PCM to the sensor. The PCM turns
P0452 and P0107 at the same time.
f Tank fuel pressure sensor malfunction may cause
P0452.
Reviewing the Failure Records vehicle mileage since the
diagnostic test last failed may help determine how often
the condition that caused the DTC to be set occurs. This
may assist in diagnosing the condition.
D06RX020