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Home >> Suzuki >> 2002 >> Esteem GL, 4D Sedan, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 1.8L >> Diagnostic Tests >> DTC P0101: Mass Air Flow Sensor - Performance Problem >> Diagnosis & Repair Procedure
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Diagnosis & Repair Procedure

  1. If engine system check has been performed, go to next step. If engine system check has not been performed, go to A4: ENGINE SYSTEM CHECK  under SYSTEM TESTS.
  2. Check MAF sensor and air intake system for blockage. Check for intake air system leaks. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, go to next step.
  3. Start engine and allow it to reach normal operating temperature. Using scan tool, read MAF SENSOR values at idle and at 2500 RPM. MAF SENSOR value should be 1.5-4.0 grams/second at idle and 5.0-10.0 grams/second at 2500 RPM. If MAF sensor values are as specified, go to step  8 . If MAF sensor values are not as specified, go to next step.
  4. Turn ignition is off. Disconnect MAF sensor 3-pin harness connector. MAF sensor is located in intake pipe at throttle body. Turn ignition on. Measure voltage between ground and MAF sensor harness connector terminal No. 3 (Red/Black wire). See Fig 1 . If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair open in Red/Black wire between MAF sensor, main relay and ECM. See WIRING DIAGRAMS article.
  5. Turn ignition off. Reconnect MAF sensor connector. Turn ignition on. Backprobbing at ECM, measure voltage between ECM harness connector C20 terminals No. 24 (Green wire) and No. 27 (Orange wire). See Figure . Voltage should be .5-1.0 volt. Start and allow engine to idle. Voltage should now be 1.3-1.8 volts. If voltage is as specified, go to next step. If voltage is not as specified, go to step  7 .
  6. Turn ignition off. Disconnect ECM 28-pin harness connector C20. ECM is located under instrument panel, behind glove box. See Figure . Check for poor terminal contact at ECM harness connector C20. If problem is found, repair as necessary. After repair, repeat DTC CONFIRMATION TEST  . If no problem is found, substitute a known good ECM, and repeat DTC CONFIRMATION TEST  .
  7. Check for open or short in Green and Orange wires between ECM harness connector C20 and MAF sensor. See WIRING DIAGRAMS article. If problem is found, repair as necessary. If no problem is found, replace MAF sensor. After repair, repeat DTC CONFIRMATION TEST  .
  8. Turn ignition on. Backprobbing at ECM, measure voltage between ECM harness connector C99 terminal No. 7 (Green wire) and ECM harness connector C20 terminal No. 27 (Orange wire). See Figure . With ignition on, voltage should be 3.9-5.0 volts. Start engine and allow it to idle. At idle, voltage should be 1.4-2.4 volts. If voltages are as specified substitute a known good ECM, and repeat DTC CONFIRMATION TEST  . If voltages are not as specified, go to next step.
  9. Check Manifold Differential Pressure (MDP) sensor. See MANIFOLD DIFFERENTIAL PRESSURE SENSOR - ESTEEM (1.8L), GRAND VITARA & VITARA in SYSTEM & COMPONENT TESTING article. If problem is found, replace as necessary. After repair, repeat DTC CONFIRMATION TEST  .
Fig 1: Identifying Mass Air Flow Sensor Harness Connector Terminals
G00163658Courtesy of SUZUKI OF AMERICA CORP.
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