MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-609
.
TROUBLESHOOTING HINTS (The most likely
causes for this code to be set are:)
•
Malfunction of the ignition switch.
•
Malfunction of the MFI relay.
•
Improper connector contact, open circuit or short-
circuited harness wire.
•
Disconnected ECM <M/T> or PCM <A/T> ground
wire.
•
Malfunction of the ECM <M/T> or PCM <A/T>.
DIAGNOSIS
STEP 1. Check connector A-18X at MFI relay for damage.
Q: Is the connector in good condition?
YES :
Go to Step 2.
NO :
Repair or replace it. Refer to GROUP 00E, Harness
Connector Inspection
. Then confirm that the
malfunction symptom is eliminated.
STEP 2. Check the MFI relay.
(1) Remove the MFI relay.
(2) Check for continuity between the MFI relay terminals 2 and
3.
•
There should be continuity. (approximately 70
Ω
)
(3) Use jumper wires to connect MFI relay terminal 2 to the
positive battery terminal and terminal 3 to the negative
battery terminal.
(4) Check the continuity between the MFI relay terminals 1 and
4 while connecting and disconnecting the jumper wire at the
negative battery terminal.
•
Should be less than 2 ohm. (Negative battery terminal
connected)
•
Should be open loop. (Negative battery terminal discon-
nected)
(5) Install the MFI relay.
Q: Is the voltage normal?
YES :
Go to Step 3.
NO :
Replace the MFI relay. Then confirm that the
malfunction symptom is eliminated.
AK101363AB
MFI RELAY
CONNECTOR: A-18X
AK101363AB
MFI RELAY
CONNECTOR: A-18X
AK101234
1 2
3 4
MFI RELAY
SIDE
CONNECTOR
AB
AK101235
1 2
3 4
MFI RELAY SIDE
CONNECTOR
AB