Acura RL. Manual - part 669

Is about -40°F (-40°C) or less, or 4.90 V or more indicated?

YES - Go to step 3. 

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals 
at ECT sensor 1 and the PCM 

3. Turn the ignition switch OFF.  

4. Disconnect ECT sensor 1 2P connector.  

5. Connect ECT sensor 1 2P connector terminals No. 1 and No. 2 with a jumper wire. 

Fig. 18: Connecting ECT Sensor 1 2P Connector Terminals No. 1 And 2 With Jumper Wire 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

6. Turn the ignition switch ON (II).  

7. Check ECT SENSOR 1 in the DATA LIST with the HDS. 

Is about -40°F( -40°C) or less, or 4.90 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 ECT sensor 1 2P connector.  

10. Turn the ignition switch ON (II).  

11. Measure voltage between ECT sensor 1 2P connector terminal No. 1 and body ground. 

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

  

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Fig. 19: Measuring Voltage Between ECT Sensor 1 2P Connector Terminal No. 1 And Body 
Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

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 PCM connector C (22P).  

15. Connect ECT sensor 1 2P connector terminal No. 2 to body ground with a jumper wire. 

Fig. 20: Connecting ECT Sensor 1 2P Connector Terminal No. 2 To Body Ground With Jumper 
Wire 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

16. Check for continuity between PCM connector terminal C12 and body ground. 

Fig. 21: Checking Continuity Between PCM Connector Terminal C12 And Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there continuity?  

YES - Go to step 25. 

NO - Repair open in the wire between the PCM (C12) and ECT sensor 1, then go to step 20.

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

  

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17. Measure voltage between PCM connector terminal A14 and body ground. 

Fig. 22: Measuring Voltage Between PCM Connector Terminal A14 And Body Ground 
Courtesy of AMERICAN HONDA MOTOR CO., INC. 

Is there about 5 V?  

YES - Repair open in the wire between the PCM (A14) and ECT sensor 1, then go to step 20. 

NO - Go to step 25. 

18. Turn the ignition switch OFF.  

19. Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ).  

20. Reconnect all connectors.  

21. Turn the ignition switch ON (II).  

22. Reset the PCM with the HDS.  

23. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).  

24. Check for Temporary DTCs or DTCs with the HDS. 

Is DTC P0118 indicated?  

YES - Check for poor connections or loose terminals at ECT sensor 1 and the PCM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the 
indicated DTCs troubleshooting 

25. Update the PCM if it does not have the latest software (see UPDATING THE PCM ), or substitute a 

known-good PCM (see SUBSTITUTING THE PCM ).  

26. Check for Temporary DTCs or DTCs with the HDS. 

Is DTC P0118 indicated?  

YES - Check for poor connections or loose terminals at ECT sensor 1 and the PCM. If the PCM was 
updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the 
PCM was substituted, go to step 1. 

NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the 
original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, 

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

  

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go to the indicated DTCs troubleshooting

DTC P0125: ECT SENSOR 1 MALFUNCTION/SLOW RESPONSE 

1. Start the engine, and let it idle 5 minutes or more.  

2. Check ECT SENSOR 1 in the DATA LIST with the HDS. 

Is about 10°F(-12°C) or less, or 4.45 V or more indicated?  

YES - Go to step 9. 

NO - Go to step 3. 

3. Allow the engine to cool to 104°F (40°C) or less.  

4. Note the value of ECT SENSOR 1 and ECT SENSOR 2 in the DATA LIST with the HDS.  

5. Start the engine, and let it idle.  

6. Let the engine idle until ECT SENSOR 1 goes up 49°F (27°C) or more from the recorded 

temperature.  

7. Note the value of ECT SENSOR 2 in the DATA LIST with the HDS.  

8. Compare ECT SENSOR 2 and the recorded temperature. 

Did ECT SENSOR 2 change 17°F (9.5°C) or more?  

YES - Intermittent failure, the system is OK at this time. Check for poor connections or loose 
terminals at ECT sensor 1, ECT sensor 2, and the PCM 

NO - Check the thermostat (see FAN MOTOR TEST ), then go to step 9. 

9. Turn the ignition switch OFF.  

10. Replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ).  

11. Turn the ignition switch ON (II).  

12. Reset the PCM with the HDS.  

13. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).  

14. Allow the engine to cool to the ambient temperature.  

15. Start the engine, and let it idle 20 minutes.  

16. Check for Temporary DTCs or DTCs with the HDS. 

Is DTC P0125 indicated?  

YES - Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM, 
then go to step 1. 

NOTE:

Before you troubleshoot, record all freeze data and any on-board snapshot, 
and review the general troubleshooting information (see GENERAL 
TROUBLESHOOTING INFORMATION ).

 

2007 Acura RL 

2005-08 ENGINE PERFORMANCE PGM-FI System - RL

  

me 

 

Friday, June 05, 2009 2:34:58 PM

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© 2005 Mitchell Repair Information Company, LLC.