MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS
TSB Revision
MULTIPORT FUEL INJECTION (MFI) <3.0L>
13B-520
STEP 1. Using scan tool MB991502, check data list item 95:
Manifold Differential Pressure Sensor.
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) Start the engine and run at idle.
(3) Set scan tool MB991502 to the data reading mode for item
95, Manifold Differential Pressure Sensor.
•
While engine is idling, pressure should be between 62
and 76 kPa.
(4) 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 :
Go to Step 2.
STEP 2. Check connector B-04 at manifold differential
pressure sensor for damage.
Q: Is the connector in good condition?
YES :
Go to Step 3.
NO :
Repair or replace it. Refer to GROUP 00E, Harness
Connector Inspection
. Then go to Step 12.
STEP 3. Check the sensor supply voltage at manifold
differential pressure sensor harness side connector B-04.
(1) Disconnect the connector B-04 and measure at the harness
side.
(2) Turn the ignition switch to "ON" position.
(3) Measure the voltage between terminal 3 and ground.
•
Voltage should be between 4.8 and 5.2 volts.
(4) Turn the ignition switch to "LOCK" (OFF) position.
Q: Is the voltage normal?
YES :
Go to Step 6.
NO :
Go to Step 4.
AKX01177
16 PIN
MB991502
AB
ACX02483
CONNECTOR : B-04
MANIFOLD
DIFFRENTIAL
PRESSURE
SENSOR
AC
AKX01427
3 2 1
B-04 HARNESS
SIDE CONNECTOR
AD