Faulty Signal
FAULTY SIGNAL
Checking Mass Air Flow Sensor
- Ignition ON.
- Mass Air Flow (MAF) Sensor connected.
- Connect a voltmeter between mass air flow (MAF) sensor connector terminals 2 and 4.
Voltmeter should read 0.1 - 0.2 Volts.
If reading is OK:
- Proceed to Check Cable for Boost Pressure Reduction section below.
If reading is incorrect:
- Proceed to test step below.
Checking the Connectors
- Ignition OFF.
- Check mass air flow (MAF) sensor and control module connectors for contact resistance and oxidation and remedy.
- Mass air flow (MAF) sensor connected.
- Engine control module (ECM) connected.
- Ignition ON.
- Connect a voltmeter between mass air flow (MAF) sensor connector terminals 2 and 4.
Voltmeter should read 0.1 - 0.2 Volts.
If reading is OK:
- The source of the diagnostic trouble code (DTC) has been loose connections in the mass air flow (MAF) sensor and/or the engine control module (ECM) connector.
If reading is incorrect:
- Try a new mass air flow (MAF) sensor.
- Then proceed to Verification section below..
Check Cable for Boost Pressure Reduction
- Ignition OFF.
- Connect the breakout box and check ground terminals.
- Disconnect engine control module (ECM).
- Ignition ON.
- Connect a voltmeter between connector #42 (#B42) on the breakout box and ground.
The voltmeter should read battery voltage.
If reading is OK:
- Proceed to test step below.
If reading is incorrect:
- Check for open-circuit between connector #42 (#B42) and supply voltage.
- Then proceed to Verification section below.
Checking the Connectors
- Ignition OFF.
- Check turbocharger (TC) control valve and engine control module (ECM) connectors for contact resistance and oxidation and remedy.
- Turbocharger (TC) control valve connected.
- Engine control module (ECM) connected.
- Ignition ON.
- Activate turbocharger (TC) control valve. See: Activating Components / Functions section.
Is the turbocharger (TC) control valve working (synchronizing)?
Yes:
- Proceed to test step below.
No:
- Try a new turbocharger (TC) control valve.
- Then proceed to Verification section below.
Checking Hoses
- Ignition OFF.
- Check that the hose between the turbocharger (TC) and turbocharger (TC) control valve, and the hose between the turbocharger (TC) control valve and pressure servo to the boost pressure control (BPC) valve are not blocked or pinched.
- Check that the turbocharger (TC) control valve is not blocked between the red and yellow connectors (when the valve is not activated, it should be open between the red and yellow connectors).
Are the hoses and turbocharger (TC) control valve OK?
Yes:
- Proceed to test step below.
No:
- Clean, replace if necessary.
- Then proceed to Verification section below.
Checking the Pressure Servo
- Ignition OFF.
- Disconnect the hose from the pressure servo.
- Connect manometer 999 5230 and pressure tester 998 5496 to pressure servo.
- Pump up a pressure of approx. 75 kPa (16.7 psi).
- The pressure servo should open fully at this pressure.
NOTE! This pressure is not an adjustment value.
- Check that the boost pressure control (BPC) valve is not sticking.
Is the pressure servo OK?
Yes:
Check the pressure servo setting.
- Then proceed to Verification section below.
No:
- Try a new pressure servo.
- Then proceed to Verification section below..
Verification
Hint: After carrying out the repair, check that the fault has been remedied as follows:
- Reconnect connectors and reinstall components.
- Erase diagnostic trouble codes (DTCs).
- Test drive the car.
- Depress the Accelerator Pedal (AP) to the floor a few times.
- Read off diagnostic trouble codes (DTOs).
EFI-414 should not be stored.
If reading is OK:
- Fault corrected.
If reading is incorrect:
- Proceed to test step below.
Fault-Tracing Information
- The verification result shows that the fault persists.
- Do you want to exit fault-tracing?
Yes:
- Fault not corrected
No:
- Return to Checking Mass Air Flow Sensor section above.