MULTIPORT FUEL INJECTION(MFI) DIAGNOSIS
MULTIPORT FUEL INJECTION (MFI) <2.4L>
M U LTIPO R T FU EL IN JEC TIO N (M FI) D IA G N O SIS
Use these steps to plan your diagnostic strategy. If
you follow them carefully, you will be sure to have
exhausted most of the possible ways to find an MFI
1. Gather as much information as possible about the
complaint from the customer.
2. Verify that the condition described by the
3. Check the vehicle for any MFI Diagnostic Trouble
4. If you cannot verify the condition and there are no
DTCs, the malfunction is intermittent. For
information on how to cope with intermittent
malfunctions, refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
to cope with Intermittent Malfunction
5. If you can verify the condition but there are no
DTCs, or the system cannot communicate with
the scan tool, refer to the trouble symptom
6. If there is a DTC, record the number of the code,
then erase the code from the memory using the
NOTE: If a DTC is erased, its "freeze frame" data will
be also erased and the readiness test status will be
reset. If necessary, store the "freeze frame" data
before erasing the DTC.
7. Reconfirm the malfunction symptom and carry out
a test drive with the drive cycle pattern.
8. If DTC is set again, carry out an inspection with
the inspection procedure for diagnostic trouble
codes of that code.
9. If DTC is not set again, the malfunction is
intermittent. For information on how to cope with
intermittent malfunctions, refer to GROUP 00,
How to Use Troubleshooting/Inspection Service
How to cope with Intermittent
10.After repairs are completed, conduct a road test
duplicating the complaint set conditions to confirm
the malfunction has been eliminated.
NOTE: If the powertrain control module (PCM) is
replaced, the immobilizer-ECU should be replaced
together with it. Each PCM has an individual
information for immobilizer-ECU, and the individual
information is registered in the immobilizer-ECU.
TROUBLE CODE DIAGNOSIS
SERVICE ENGINE SOON/MALFUNCTION INDICATOR
Among the on-board diagnostic items, a Service Engine Soon/
Malfunction Indicator Lamp illuminates to notify the driver of an
emission control malfunction.
However, when an irregular signal returns to normal and the
engine control module judges that it has returned to normal, the
Service Engine Soon/Malfunction Indicator Lamp is switched
Moreover, when the ignition switch is turned off, the lamp is
switched off. Even if the ignition switch is turned on again, the
lamp does not illuminate until the malfunction is detected.
Immediately after the ignition switch is turned on, the Service
Engine Soon/Malfunction Indicator Lamp is lit for five seconds
to indicate that the Service Engine Soon/Malfunction Indicator
Lamp operates normally.
Items Indicated by the Service Engine Soon/Malfunction Indicator Lamp
SERVICE ENGINE SOON/
Powertrain control module (PCM) malfunction
Volume air flow circuit range/performance problem
Volume air flow circuit low input