Diagnostic Trouble Code (Dtc) P0108 Manifold Absolute Pressure (Map) Circuit High Input - Isuzu 1999 RODEO Workshop Manual

DIAGNOSTIC TROUBLE CODE (DTC) P0108 MANIFOLD ABSOLUTE PRES-
Circuit Description
The manifold absolute pressure (MAP) sensor responds
to changes in intake manifold pressure. The MAP sensor
signal voltage to the powertrain control module (PCM)
varies from below 2 volts at idle (low manifold pressure) to
above 4 volts with the ignition ON, engine not running or at
wide–open throttle (high manifold pressure).
A "speed density" method of determining engine load is
used on the 2.2L engine. This is calculated using inputs
from the MAP sensor, RPM, CKP Sensor, and the Intake
Air Temperature (IAT) sensor. The MAP sensor is the
main sensor used in this calculation, and measuring
engine load is its main function. The MAP sensor is also
used to determine manifold pressure changes while the
exhaust gas recirculation (EGR) flow test diagnostic is
being run, to determine engine vacuum level for some
other diagnostics and to determine barometric pressure
(BARO). Refer to DTC P0401.
The PCM monitors the MAP signals for voltages outside
the normal range (10–104 kpa) of the MAP sensor. If the
PCM detects a MAP signal voltage that is excessively
low, Diagnostic Trouble Code P0108 will be set. DTC
P0108 is a Type A Code.
Conditions for Setting the DTC
f No TP sensor Diagnostic Trouble Codes present.
f Engine is running.
RODEO X22SE 2.2L ENGINE DRIVEABILITY AND EMISSION
SURE (MAP) CIRCUIT HIGH INPUT
f Throttle position is below 2.7% if engine speed is below
1000 RPM.
f Throttle position is below 10% if engine speed is above
1000 RPM.
f The MAP sensor indicates manifold absolute pressure
above 90 kPa for a total of approximately 10 seconds
over a 16–second period.
Action Taken When the DTC Sets
f The PCM will illuminate the malfunction indicator lamp
(MIL) after the second consecutive trip in which the
fault is detected.
f The PCM will default to a BARO value of 79.3 kPa.
f The PCM will store conditions which were present
when the Diagnostic Trouble Code was set as Freeze
Frame and in the 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 Diagnostic Trouble Code P0108 will clear
after 40 consecutive warm–up cycles have occurred
without a fault.
f Diagnostic Trouble Code P0108 can be cleared by
using the Scan Tool's "Clear Info" function.
Diagnostic Aids
Check for the following conditions:
6E1–117
D06RX042