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Code 5 - Map Sensor

  1. Turn ignition off. Remove appropriate fuse for 10 seconds to reset ECU. See CLEARING CODES  . Start engine. Verify if CHECK ENGINE light is flashing Code 5. If Code 5 is present, go to next step. If Code 5 is not present, problem is intermittent. Check vacuum hoses, pipes and connections. Ensure all connectors are secure.
  2. Turn ignition off. Using a "T" fitting, connect a hand-held vacuum pump/gauge into vacuum hose between throttle body and MAP sensor (vacuum hose No. 21). Apply vacuum. If vacuum does not hold, attach vacuum pump/gauge directly to MAP sensor. Apply vacuum. If vacuum does not hold, replace MAP sensor. If vacuum holds, check MAP sensor vacuum hose for cracks, splits and looseness. Repair as necessary.
  3. Check vacuum supply to MAP sensor with engine running. If vacuum is not present, repair hose or clear restriction from throttle body. If vacuum supply is okay, turn ignition off.
  4. Connect appropriate ECU Test Harness (07LAJ-PT3010A ) between ECU and ECU connector. See Figure . Measure voltage between terminal D17 and terminal D21. See Figure . If voltage reading is about 3 volts, go to next step. If voltage is not about 3 volts, replace MAP sensor.
  5. Start engine, and let idle. If voltage is not about 1 volt, replace MAP sensor. If voltage reading is about 1 volt, substitute a known good ECU. If condition is corrected, replace original ECU.
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