MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-567
STEP 1. Using scan tool MB991502, read the diagnostic
trouble code (DTC).
CAUTION
To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Read the DTC.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC output?
YES :
Refer to, Diagnostic Trouble Code Chart
.
NO :
Go to Step 2.
STEP 2. Check the idle air control (IAC) motor operation
sound.
(1) Check that the engine coolant temperature is 20
°
C (68
°
F)
or below.
NOTE: If necessary, you can disconnect the engine coolant
temperature sensor connector and connect the harness
side of the connector to another engine coolant temperature
sensor that is at 20
°
C (68
°
F) or below.
(2) Check that the operation sound of the IAC motor can be
heard after the ignition is switched to the "ON" position (but
without starting the engine).
•
An operation sound should be heard.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Did you hear the operation sound?
YES :
Go to Step 3.
NO :
Refer to, DTC P0506
−
Idle Control System RPM
Lower Than Expected
, DTC P0507
−
Idle
Control System RPM Higher Than Expected
.
STEP 3. Using scan tool MB991502, check data list.
CAUTION
To prevent damage to scan tool MB991502, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991502.
(1) Connect scan tool MB991502 to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check the following items in the data list. Refer to, Data List
Reference Table
a. Item 21: Engine Coolant Temperature Sensor.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Are they operating properly?
YES :
Go to Step 4.
NO :
Repair or replace. Then confirm that the malfunction
symptom is eliminated.
AKX01177
16 PIN
MB991502
AB
ACX02523AI
IDLE AIR
CONTROL
MOTOR
CONNECTOR:B-34
AKX01177
16 PIN
MB991502
AB