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Home >> Acura >> 1995 >> Integra GS-R, 4D Sedan >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Trouble Codes >> Code 3 - Manifold Absolute Pressure (Map) Sensor
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Code 3 - Manifold Absolute Pressure (Map) Sensor

  1. Turn ignition off. Remove BACK-UP fuse (7.5-amp) from underhood fuse box for 10 seconds to reset ECM. Start and idle engine. Retrieve codes. If Code 3 does not exist, problem is intermittent. Inspect for poor or loose connections at MAP sensor and ECM. Test-drive vehicle and retest.
  2. If Code 3 exists, turn ignition off. Unplug 3-pin MAP sensor connector. Turn ignition on. Measure voltage between MAP sensor Yellow/Red or Yellow/White wire (positive) and any body ground. See Fig 1 . If voltage is about 5 volts, go to step 4). If volt age is not about 5 volts, attach connector "D" of ECM Test Harness (07LAJ-PT3010A ) to ECM, leaving vehicle wiring harness disconnected.
    Fig 1: Locating MAP Sensor & Connector Terminal ID
    G94D44340Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Turn ignition on. Measure voltage between test terminals D19 (+) and D21 (-). If voltage is about 5 volts, repair open circuit in D19 (Yellow/Red or Yellow/White wire) between ECM connector and MAP sensor. If voltage is not about 5 volts, temporarily substitute known good ECM, then retest system.
  4. Measure voltage between Yellow/Red or Yellow/White (+) and Green/White (-) wires at MAP sensor. If voltage is not about 5 volts, repair open in Green/White wire between ECM terminal D21 and MAP sensor. If voltage is about 5 volts, measure voltage between White/Yellow (+) and Green/White (-) wire terminals at MAP sensor.
  5. If voltage is about 5 volts, go to next step. If voltage is not about 5 volts, measure voltage between test harness terminals D17 and D21. See Figure . If voltage is about 5 volts, repair open or short in circuit D17 (White/Yellow wire) between ECM connector and MAP sensor. If voltage is not about 5 volts, temporarily substitute known good ECM, then retest system. If voltage is not about 5 volts, replace MAP sensor.
  6. Turn ignition off. Reconnect wiring to MAP sensor. Connect ECM Test Harness (07LAJ-PT3010A ) between ECM and ECM connectors. Turn ignition on. Measure voltage between test terminals D17 and D21. If voltage is not about 3 volts, replace MAP sensor. If voltage is about 3 volts, temporarily substitute known good ECM, then retest system.