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Home >> Acura >> 1988 >> Legend Base, 2D Coupe, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Tests W/Codes >> Self-Diagnostic System >> Code 13 - Atmosphere Sensor
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Code 13 - Atmosphere Sensor

  1. Turn ignition off. Disconnect alternator sense fuse in under-hood relay box for 10 seconds to reset ECU. Start engine and observe PGM-FI warning light. If light is off, problem is intermittent. Test drive and check again.
  2. If light is on, turn ignition off. Connect system checker harness between ECU and ECU connector. Turn ignition on. Measure voltage between ECU terminals C13 (pos.) and C14 (neg.). If about 5 volts is indicated, go to step 3). If not, substitute a known ECU and recheck. If specified voltage in now available, replace original ECU.
  3. Measure voltage between terminals C9 (pos.) and C14 (neg.). If about 3 volts is not indicated, go to step 4). If about 3 volts is indicated, substitute a known good ECU and recheck. If condition is rectified, replace original ECU.
  4. Disconnect connector from atmospheric pressure sensor. Measure voltage between terminals C9 (pos.) and C14 (neg.) on harness side. If about 5 volts is indicated, go to step 5). If about 5 volts is not indicated, repair short in Red wire between ECU terminal C9 and sensor.
  5. Measure voltage between Yellow/White (pos.) and Green/White (neg.) wires. If reading is not about 5 volts, go to step 6). If about 5 volts is present, measure voltage between Red (pos.) and Green/White (neg.) terminals. If about 5 volts is not read, repair open in Red wire between ECU terminal C9 and sensor. If about 5 volts is read, replace sensor.
  6. Measure voltage between ground and Yellow/White wire of harness. If about 5 volts is not present, repair open in Yellow/White wire between ECU terminal C13 and sensor. If about 5 volts is present, repair open in Green/White wire between ECU terminal C14 and sensor.
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