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Home >> Saab >> 2001 >> 9-5 Base, 4D Sedan, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Fault Code Diagnosis >> P0103: Mass Air Flow Circuit - High Input >> Fault Isolation Procedure

Fault Isolation Procedure

  1. Checking the sensor's power supply:
    • Turn the ignition switch to the ON position.
    • Unplug the connector: Mass air flow sensor (205).
    • Connect Test Lamp (86 1 857) to pin 3 of the female connector and a good grounding point.
    • Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.
    If the test lamp illuminates, go to step  3, otherwise go to next step.
  2. Rectifying the lead: The lead from crimp connection J24 to pin 3 of the female connector is faulty. Rectify and go to step  8.
  3. Checking the sensor's grounding:
    • Connect Test Lamp (86 1 857) to pins 3 and 2 of the female connector.
    • Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.
    If the test lamp illuminates, go to step  5, otherwise go to next step.
  4. Rectifying the lead: The lead from crimp connection J15 to pin 2 of the female connector is faulty. Rectify and go to step  8.
  5. Checking the control module's sensor input:
    • Take a voltage reading: (1,2) Mass air flow sensor (205:1 & 205:2).
    • Jiggle the leads and in-line connectors at several places and in different directions to reveal intermittent breaks and short circuits in the wiring harness. Observe the multimeter, test lamp or diagnostic tool while doing this.
    If the reading shows 4.9-5.1 volts, go to step  7, otherwise go to next step.
  6. Rectifying the lead: The lead from pin 1 of the female connector to pin 65 of the control module is faulty. Rectify and go to step  8.
  7. Changing components: Change the mass air flow sensor. When finished, go to next step.
  8. Final check:
    • Clear the DTCs in all systems.
    • Carry out a drive cycle: Drive the car at varying engine loads and engine RPM for 5 minutes.
    • Evaluate the drive cycle: Check that the DTC has not recurred.
    If the trouble code has recurred, the ECM is probably at fault and will need replacement. Replace with known-good ECM and retest. if no DTCs are present, then the steps taken to rectify the fault were correct.
Fig 1: Mass Air Flow Circuit
G00207341Courtesy of SAAB-SCANIA OF AMERICA, INC.
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