Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual - part 230
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L ENGINE>
13B-119
CIRCUIT OPERATION
•
A voltage corresponding to the oxygen
concentration in the exhaust gas is sent to the
ECM (terminal 72) <M/T> or PCM (terminal 72)
<A/T> from the output terminal (terminal 4) of the
right bank heated oxygen sensor (front).
•
Terminal 2 of the right bank heated oxygen
sensor (front) is grounded with ECM (terminal 49)
<M/T> or PCM (terminal 57) <A/T>.
TECHNICAL DESCRIPTION
•
The right bank heated oxygen sensor (front)
detects the concentration of oxygen in the
exhaust gas; it converts those data to voltage,
and inputs the resulting signals to the ECM <M/
T> or PCM <A/T>.
•
When the right bank heated oxygen sensor
(front) begins to deteriorate, the heated oxygen
sensor signal response becomes poor.
•
The ECM <M/T> or PCM <A/T> forcibly varies
the air/fuel mixture to make it leaner and richer,
and checks the response speed of the right bank
heated oxygen sensor (front). In addition, the
ECM <M/T> or PCM <A/T> also checks for an
open circuit in the right bank heated oxygen
sensor (front) output line.
DTC SET CONDITIONS
Check Conditions
•
Engine coolant temperature is higher than 50
°
C
(176
°
F).
•
Engine speed is at between 1,250 and 3,000 r/
min.
•
Volumetric efficiency is at between 20 and 60
percent.
•
Intake air temperature is higher than -10
°
C (14
°
F).
•
Barometric pressure is higher than 76 kPa (11
psi).
•
Under the closed loop air/fuel control.
•
ECM <M/T> or PCM <A/T> dose not judge to be
idling state.
Judgment Criteria
•
The right bank heated oxygen sensor (front)
sends "lean" and "rich" signals alternately 10
times (Response time 1.2 or equivalent) or less
for 12 seconds.
•
Only one monitor during one drive cycle
NOTE: If the sensor switch time is longer than the
Judgment Criteria due to the MUT-II OBD-II test
Mode
−
H02S Test Results, it is assumed that the
heated oxygen sensor has deteriorated. If it is
short, it is assumed that the harness is damaged
or has a short circuit.
If the heated oxygen sensor signal voltage has
not changed even once (lean/rich) after the DTC
was erased, the sensor switch time will display as
0 seconds.
TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are:)
•
Right bank heated oxygen sensor (front)
deteriorated.
•
Open circuit in right bank heated oxygen sensor
(front) output line.
•
Open circuit in right black heated oxygen sensor
(front) ground line.
•
ECM failed. <M/T>
•
PCM failed. <A/T>
DIAGNOSIS
Required Special Tools
MB991502: Scan Tool (MUT-II)
ACX02481
CONNECTOR : B-27
RIGHT BANK
HEATED OXYGEN
SENSOR(FRONT)
AC
AK000225
CONNECTORS : C-58, C-62<M/T>,
C-55, C-59<A/T>
C-55
C-58
PCM<A/T>
ECM<M/T>
AK
C-59
C-62