Mitsubishi Eclipse / Eclipse Spyder (2000-2002). Service and repair manual - part 111
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <2.4L ENGINE>
13A-143
CIRCUIT OPERATION
•
A voltage corresponding to the oxygen
concentration in the exhaust gas is sent to the
ECM (terminal 75) <M/T> or PCM (terminal 73)
<A/T> from the output terminal (terminal 3) of the
heated oxygen sensor (rear).
•
Terminal 4 of the heated oxygen sensor (rear) is
grounded with ECM (terminal 92) <M/T> or PCM
(terminal 57) <A/T>.
TECHNICAL DESCRIPTION
•
The output signal of the heated oxygen sensor
(front) is compensated by the output signal of the
heated oxygen sensor (rear).
•
The ECM <M/T> or PCM <A/T> checks for an
open circuit in the heated oxygen sensor (rear)
output line.
DTC SET CONDITIONS
Check Conditions
•
Engine coolant temperature is higher than 82
°
C
(180
°
F).
•
Barometric pressure is higher than 76 kPa (11
psi).
•
The heated oxygen sensor (front) is active.
Judgement Criteria
•
The heated oxygen sensor (rear) output voltage,
before the fuel shut off is started, was 0.4 volts or
more, and during the shut off, it takes one second
or more for the heated oxygen sensor (rear)
output voltage to fall from 0.4 to 0.15 volts.
or
•
The heated oxygen sensor (rear) output voltage,
before the fuel shut off is started, was 0.15 volts
or more, and during the shut off, it takes three
seconds or more for the heated oxygen sensor
(rear) output voltage to fall below 0.15 volts.
TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are:)
•
Heated oxygen sensor (rear) failed.
•
Open circuit in heated oxygen sensor (rear)
output line.
•
Open circuit in heated oxygen sensor (rear)
ground line.
•
ECM failed. <M/T>
•
PCM failed. <A/T>
DIAGNOSIS
Required Special Tools
MB991502: Scan Tool (MUT-II)
STEP 1. Using scan tool MB991502, check data list item 59:
Heated Oxygen Sensor (rear).
CAUTION
To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Start the engine and run at idle.
(3) Set scan tool MB991502 to the data reading mode for item
59, Heated Oxygen Sensor (rear).
(4) Warm up the engine.
•
After increasing the output voltage 0.15 volts or more by
the engine revving, finish it. Then confirm that the output
voltage reduces to 0.15 volts or less within 3 seconds.
(5) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor operating properly?
YES : It can be assumed that this malfunction is intermittent.
Refer to GROUP 00, How to Use Troubleshooting/
Inspection Service Points (
NO : Replace the heated oxygen sensor (rear). Then go to
Step 2.
AKX01177
16 PIN
MB991502
AB