DTC P0148:00 [MZI-3.7 (PCM CONNECTOR (3 TYPES))]


id0102e4312000

DTC P0148:00

Fuel delivery error

DETECTION CONDITION
•  At least 1 bank is lean at wide open throttle (WOT).
POSSIBLE CAUSE
•  Damaged or worn fuel pump
•  Damaged or contaminated MAF sensor
•  Severely restricted fuel filter
•  Severely restricted fuel supply line
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT SYSTEM INTEGRITY
•  Visually inspect the complete fuel delivery system for damage and leakage.
•  Check the following:
―  Fuel lines and connections
―  Relays
―  Fuel tank
―  Fuel pump
―  Fuel pressure regulator
―  Fuel pulse damper
―  Fuel rail at fuel injectors
―  Damaged connector pins
―  Electrical connectors not fully engaged
•  Verify that the vehicle has followed the maintenance schedule (For Mexico specs.).
•  Verify that the fuse integrity.
•  Verify that the battery is fully charged.
•  Verify that there is clean sufficient fuel.
•  Is a concern present?
Yes
Repair if necessary. Then go to Step 11.
No
Go to the next step.
4
INSPECT FUEL PRESSURE
•  Turn the ignition switch off.
•  Relieve the fuel pressure. Refer to the Workshop Manual Fuel System Pressure Release procedure.
•  Connect the mechanical fuel pressure gauge.
•  Turn the ignition switch to the ON position (engine off).
•  Pressurize the fuel system. Refer to the “FUEL LINE PRESSURE INSPECTION”.
•  Compare the fuel pressure reading to the Fuel line pressure Specification.
Fuel line pressure
375—450 kPa {3.83—4.58 kgf/cm2, 54.4—65.2 psi}
•  Is the fuel pressure within range?
Yes
Go to Step 8.
No
Go to the next step.
5
INSPECT FUEL PUMP GROUND CIRCUIT FOR OPEN CIRCUIT IN WIRING HARNESS
Note
•  Refer to the Wiring Diagrams Manual for schematic and connector information.
•  Disconnect the fuel pump connector.
•  Measure the voltage between fuel pump connector terminal D (wiring harness-side) and battery positive terminal.
•  Is the voltage more than 10 V?
Yes
Go to the next step.
No
Repair or replace suspected part, Then go to Step 11.
6
INSPECT FUEL PUMP POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT IN WIRING HARNESS
•  Access the fuel pump connector.
•  Turn the ignition switch to the ON position (engine running).
•  Measure the voltage between fuel pump connector terminal B (wiring harness-side) and body ground.
•  Is the voltage more than 10 V?
Yes
Go to the next step.
No
Repair or replace suspected part, Then go to Step 11.
7
INSPECT FUEL PRESSURE LEAK
•  Connect the mechanical fuel pressure gauge.
•  Turn the ignition switch to the ON position (engine running).
•  Allow the fuel pressure to stabilize.
•  Record the stabilized reading.
•  Turn the ignition switch off.
•  Monitor the fuel pressure for 1 min.
•  Does the fuel pressure remain within 34 kPa {255 mmHg, 10.0 inHg} of the recorded reading after 1 min?
Yes
Perform the KOEO self-test.
Go to Step 9.
No
Go to the next step.
8
INSPECT FUEL INJECTOR OPERATION
•  Perform the Fuel Injector Operation Inspection.
•  Do the fuel injectors operate properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the inspection results, then go to Step 11.
9
INSPECT FUEL SUPPLY LINE FOR RESTRICTION
Note
•  Observe the Warnings, Cautions, and Notes, referring to “BEFORE SERVICE PRECAUTION” and “AFTER SERVICE PRECAUTION”.
•  Disconnect the fuel supply line at the fuel rail.
•  Disconnect the fuel supply line at the fuel pump.
•  Check the fuel supply line for restriction.
•  Apply 21—34 kPa {2142—3467 mmHg, 84.34—136.4 inHg} air pressure to the fuel supply line.
•  Does air flow freely through the line?
Yes
Go to the next step.
No
Repair the cause of the restriction. Then go to Step 12.
10
VERIFY THE REPAIR
Warning
•  Strict observance of posted speed limits and attention to driving conditions are mandatory when carrying out the road test. Failure to follow these instructions may result in personal injury.
•  Turn the ignition switch to the ON position, Key ON, engine running.
Engine at normal operating temperature
Monitor the mechanical gauge
From a stop, accelerate to 89 km/h (55 mph) at full throttle. Repeat this 3 times.
Is the fuel pressure always greater than 240 kPa {2.45 kgf/cm2, 34.8 psi}?
Yes
The test is complete and no concerns are present.
No
Replace the fuel pump module. Then go to the next step.
11
VERIFY TROUBLESHOOTING OF DTC P0148:00 HAS BEEN COMPLETED
•  Verify that all disconnected connectors are reconnected.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Start the engine and run it at idle.
•  Retrieve DTCs using the M-MDS.
•  Is the PENDING CODE for this DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
Troubleshooting completed.