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Home/Acura/RSX/Acura RSX I facelift (2004-2006)/Repair manual/Testing & Diagnostics/DTC P0111, P1116: IAT Sensor Circuit Range/Performance Prob…
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DTC P0111, P1116: IAT Sensor Circuit Range/Performance Problem (2005-2006 models); ECT Sensor Circuit Range/Performance Problem (2005-2006 models) Acura RSX I facelift

Testing & Diagnostics 12 illustrations ~2062 words
  1. Check for poor connections or loose terminals at the ECT sensor and the IAT sensor. Are the connections and terminals OK? YES - Go to step 2. NO - Repair the connectors or terminals, then go to step 25 .
  2. Start the engine, and let it idle for 10 minutes.
  3. Check the ECT SENSOR in the DATA LIST with the HDS. Is about 129°F (54°C) or less, or 1.54 V or more indicated? YES - Replace the ECT sensor (see «CKP SENSOR REPLACEMENT»(ref-218785-S26595789332006021000000) ), then go to step 25 . NO - Go to step 4.
  4. Turn the ignition switch OFF.
  5. Remove the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).
  6. Allow the IAT sensor to cool to 77°F (25°C).
  7. Note the ambient temperature.
  8. Connect the IAT sensor to the 2P connector. Do not install the sensor on the air intake duct.
  9. Turn the ignition switch ON (II).
  10. Note the value of the IAT SENSOR quickly in the DATA LIST with the HDS.
  11. Compare the IAT SENSOR and the ambient temperature. Does the IAT SENSOR differ 5.4°F (3°C) or more? YES - Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ), then go to step 25 . NO - Go to step 12.
  12. Disconnect the IAT sensor from the 2P connector.
  13. Using a heat gun, blow hot air on the IAT sensor for a few seconds. Do not apply the heat longer than a few seconds or you will damage the sensor.
  14. Connect the IAT sensor to the 2P connector. Do not install the sensor on the air intake duct.
  15. Check the IAT SENSOR in the DATA LIST with the HDS. Does the IAT SENSOR change 82°F (28°C) or more? YES - Go to step 16. NO - Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ), then go to step 25 .
  16. Turn the ignition switch OFF.
  17. Drain the coolant (see «COOLANT CHECK»(ref-218781-S40044508412006021000000) ).
  18. Remove the ECT sensor (see «CKP SENSOR REPLACEMENT»(ref-218785-S26595789332006021000000) ).
  19. Allow the ECT sensor to cool to 77°F (25°C).
  20. Note the ambient temperature.
  21. Connect the ECT sensor to the 2P connector. Do not install the sensor on the engine.
  22. Turn the ignition switch ON (II).
  23. Note the value of ECT SENSOR quickly in the DATA LIST with the HDS.
  24. Compare the ECT SENSOR and the ambient temperature. Does the ECT SENSOR differ 5.4°F (3°C) or more? YES - Replace the ECT sensor (see «CKP SENSOR REPLACEMENT»(ref-218785-S26595789332006021000000) ), then go to step 25. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the ECT sensor and the ECM/PCM.
  25. Turn the ignition switch ON (II).
  26. Reset the ECM/PCM with the HDS.
  27. Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(ref-218787-S18900728242006021000000) ).
  28. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0111 and/or P1116 is indicated, check for poor connections or loose terminals at the ECT sensor, or the IAT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated «DTC'S TROUBLESHOOTING»(ref-218785-S20313967292006021000000) . NO - Troubleshooting is complete.

Scheme 111

Scheme 111: DTC P0112: IAT Sensor Circuit Low Voltage (2002-2004 models)
Scheme 111: DTC P0112: IAT Sensor Circuit Low Voltage (2002-2004 models)
  1. Turn the ignition switch ON (II).
  2. Check the IAT with a scan tool or the HDS. Is 302°F (150°C) or higher, or 0 V indicated? YES - Go to step 3. NO - Go to step 10 .
  3. Turn the ignition switch OFF.
  4. Disconnect the IAT sensor 2P connector.
  5. Turn the ignition switch ON (II).
  6. Check the IAT with a scan tool or the HDS. Is 302°F (150°C) or higher, or 0 V indicated? YES - Go to step 7. NO - Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).
  7. Turn the ignition switch OFF.
  8. Disconnect ECM/PCM connector B (24P).
  9. Check for continuity between IAT sensor 2P connector terminal No. 2 and body ground. Is there continuity? YES - Repair short in the wire between the ECM/PCM (B17) and the IAT sensor. NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO UPDATE THE ECM/PCM»(ref-218783-S21903648732006021000000) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(ref-218785-S00586955502006021000000) ).
  10. Check the temperature reading on a scan tool or the HDS. Be aware that if the engine is warm, the reading will be higher than ambient temperature. If the engine is cold, the IAT and ECT will have the same value. Is the correct ambient temperature indicated? YES - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAT sensor and the ECM/PCM. NO - Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).

Scheme 112

Scheme 112: DTC P0112: IAT Sensor Circuit Low Voltage (2005-2006 models)
Scheme 112: DTC P0112: IAT Sensor Circuit Low Voltage (2005-2006 models)
  1. Turn the ignition switch ON (II).
  2. Check the IAT SENSOR in the DATA LIST with the HDS. Is about 356°F (180°C) or higher, or 0.08 V or less indicated? YES - Go to step 3. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAT sensor and the ECM/PCM.
  3. Turn the ignition switch OFF.
  4. Disconnect the IAT sensor 2P connector.
  5. Turn the ignition switch ON (II).
  6. Check the IAT SENSOR in the DATA LIST with the HDS. Is about 356°F (180°C) or higher, or 0.08 V or less indicated? YES - Go to step 7. NO - Go to step 11 .
  7. Turn the ignition switch OFF.
  8. Jump the SCS line with the HDS.
  9. Disconnect ECM/PCM connector B (24P).
  10. Check for continuity between IAT sensor 2P connector terminal No. 2 and body ground. Is there continuity? YES - Repair short in the wire between the IAT sensor and the ECM/PCM (B17), then go to step 13 . NO - Go to step 18 .
  11. Turn the ignition switch OFF.
  12. Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).
  13. Reconnect all connectors.
  14. Turn the ignition switch ON (II).
  15. Reset the ECM/PCM with the HDS.
  16. Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(ref-218787-S18900728242006021000000) ).
  17. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0112 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated «DTC'S TROUBLESHOOTING»(ref-218785-S20313967292006021000000) . NO - Troubleshooting is complete.
  18. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO UPDATE THE ECM/PCM»(ref-218783-S21903648732006021000000) ).
  19. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0112 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated «DTC'S TROUBLESHOOTING»(ref-218785-S20313967292006021000000) . NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(ref-218785-S00586955502006021000000) ).

Scheme 113

Scheme 113: DTC P0113: IAT Sensor Circuit High Voltage (2002-2004 models)
Scheme 113: DTC P0113: IAT Sensor Circuit High Voltage (2002-2004 models)

Scheme 114

Scheme 114
Scheme 114

Scheme 115

Scheme 115
Scheme 115

Scheme 116

Scheme 116
Scheme 116

Scheme 117

Scheme 117
Scheme 117
  1. Turn the ignition switch ON (II).
  2. Check the IAT with a scan tool or the HDS. Is -4°F ( -20°C) or less, or 5 V indicated? YES - Go to step 3. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAT sensor and the ECM/PCM.
  3. Turn the ignition switch OFF.
  4. Disconnect the IAT sensor 2P connector.
  5. Connect IAT sensor 2P connector terminals No. 1 and No. 2 with a jumper wire.
  6. Turn the ignition switch ON (II).
  7. Check the IAT with a scan tool or the HDS. Is -4°F ( -20°C) or less, or 5 V indicated? YES - Go to step 8. NO - Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).
  8. Turn the ignition switch OFF.
  9. Remove the jumper wire.
  10. Turn the ignition switch ON (II).
  11. Measure voltage between IAT sensor 2P connector terminal No. 2 and body ground. Is there about 5 V? YES - Go to step 12. NO - Go to step 15 .
  12. Turn the ignition switch OFF.
  13. Connect IAT sensor 2P connector terminal No. 1 to body ground with a jumper wire.
  14. Check for continuity between ECM/PCM connector terminal A10 and body ground. Is there continuity? YES - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO UPDATE THE ECM/PCM»(ref-218783-S21903648732006021000000) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(ref-218785-S00586955502006021000000) ). NO - Repair open in the wire between the ECM/PCM (A10) and the IAT sensor.
  15. Measure voltage between ECM/PCM connector terminal B17 and body ground. Is there about 5 V? YES - Repair open in the wire between the ECM/PCM (B17) and the IAT sensor. NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO UPDATE THE ECM/PCM»(ref-218783-S21903648732006021000000) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(ref-218785-S00586955502006021000000) ).

Scheme 118

Scheme 118: DTC P0113: IAT Sensor Circuit High Voltage (2005-2006 models)
Scheme 118: DTC P0113: IAT Sensor Circuit High Voltage (2005-2006 models)

Scheme 119

Scheme 119
Scheme 119

Scheme 120

Scheme 120
Scheme 120

Scheme 121

Scheme 121
Scheme 121

Scheme 122

Scheme 122
Scheme 122
  1. Turn the ignition switch ON (II).
  2. Check the IAT SENSOR in the DATA LIST with the HDS. Is about -40°F ( -40°C) or less, or 4.92 V or more indicated? YES - Go to step 3. NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAT sensor and the ECM/PCM.
  3. Turn the ignition switch OFF.
  4. Disconnect the IAT sensor 2P connector.
  5. Connect IAT sensor 2P connector terminals No. 1 and No. 2 with a jumper wire.
  6. Turn the ignition switch ON (II).
  7. Check the IAT SENSOR in the DATA LIST with the HDS. Is about -40°F ( -40 °C) or less, or 4.92 V or more indicated? YES - Go to step 8. NO - Go to step 18 .
  8. Turn the ignition switch OFF.
  9. Remove the jumper wire from the IAT sensor 2P connector.
  10. Turn the ignition switch ON (II).
  11. Measure voltage between IAT sensor 2P connector terminal No. 2 and body ground. Is there about 5 V? YES - Go to step 12. NO - Go to step 17 .
  12. Turn the ignition switch OFF.
  13. Jump the SCS line with the HDS.
  14. Disconnect ECM/PCM connector A (31P).
  15. Connect IAT sensor 2P connector terminal No. 1 to body ground with a jumper wire.
  16. Check for continuity between ECM/PCM connector terminal A23 and body ground. Is there continuity? YES - Go to step 25 . NO - Repair open in the wire between the ECM/PCM (A23) and the IAT sensor, then go to step 20 .
  17. Measure voltage between ECM/PCM connector terminal B17 and body ground. Is there about 5 V? YES - Repair open in the wire between the ECM/PCM (B17) and the IAT sensor, then go to step 20 . NO - Go to step 25 .
  18. Turn the ignition switch OFF.
  19. Replace the IAT sensor (see «CMP SENSOR B REPLACEMENT»(ref-218785-S27831913012006021000000) ).
  20. Reconnect all connectors.
  21. Turn the ignition switch ON (II).
  22. Reset the ECM/PCM with the HDS.
  23. Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(ref-218787-S18900728242006021000000) ).
  24. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0113 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated «DTC'S TROUBLESHOOTING»(ref-218785-S20313967292006021000000) . NO - Troubleshooting is complete.
  25. Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO UPDATE THE ECM/PCM»(ref-218783-S21903648732006021000000) ).
  26. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0113 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated «DTC'S TROUBLESHOOTING»(ref-218785-S20313967292006021000000) . NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(ref-218785-S00586955502006021000000) ).

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