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Code 10, Air Temperature (Ta) Sensor

  1. Turn off ignition. Remove clock fuse in the 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. Measure resistance across TA sensor terminals. If reading is not 1000-4000 ohms, replace sensor. If resistance is within specification, measure voltage between ground and White/Red wire terminal. If reading is about 5 volts, go to step 3). If reading is not about 5 volts, go to step 4).
  3. Measure voltage between same wire (pos.) and Green/White (neg.) wire terminal. If voltage is not about 5 volts, repair open in Green/White between ECU terminal C12 and sensor. If reading is about 5 volts, substitute a known good ECU. If condition is rectified, replace original ECU.
  4. If voltage in step 2) was not about 5 volts, turn ignition off. Connect system checker harness between ECU and ECU connector. Turn ignition on. Measure voltage between terminals C5 (pos.) and C12 (neg.). If voltage reading is about 5 volts, repair open in White/Red wire between ECU terminal C5 and sensor.
  5. If reading was not about 5 volts, disconnect "C" connector from the main wire harness only, not the ECU. Measure voltage between terminals C5 (pos.) and C12 (neg.). If voltage reading is about 5 volts, repair short in White/Red wire between ECU terminal C5 and sensor.
  6. If voltage is not about 5 volts, substitute a known good ECU. If voltage is now correct, replace original ECU.
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