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Idle Control System Acura TL III

Testing & Diagnostics 22 illustrations ~3420 words

Scheme 478

Scheme 478: Component Location Index
Scheme 478: Component Location Index
CAUTIONDo not insert your fingers into the installed throttle body when you turn the ignition switch ON (II) or while the ignition switch is ON (II). If you do, you will seriously injure your fingers if the throttle valve is activated.

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

  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  4. Check for these conditions in the DATA LIST with the HDS: Engine coolant temperature above 156 °F (70 °C) Intake air temperature above 32 °F (0 °C) Vehicle speed is 0 mph (0 km/h) ST FUEL TRIM between 0.69 and 1.47 FSS is CLOSED
  5. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS. Does the screen indicate FAILED? YES -Go to step 6. NO -If the screen indicates PASSED, go to step 15. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, go to step 4 and recheck.
  6. Remove the intake air duct from the throttle body.
  7. Check for dirt, carbon, or damage in the throttle bore. Is there dirt, carbon, or damage in the throttle bore? YES -If there is dirt or carbon, clean the throttle body (see «THROTTLE BODY TEST»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#intake-air-system) ), and also check for damage at the air cleaner element (see «AIR CLEANER REMOVAL/INSTALLATION»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#intake-air-system) ), then go to step 9. If there is damage in the throttle bore, go to step 8. NO -Check the A/C system or power steering system, then go to step 17.
  8. Replace the throttle body (see «THROTTLE BODY REMOVAL/INSTALLATION»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#intake-air-system__throttle-body-removalinstallation) ).
  9. Reset the ECM/PCM with the HDS.
  10. Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#idle-control-system__ecmpcm-idle-learn-procedure) ).
  11. Start the engine, Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  12. Check this data in the DATA LIST with the HDS: Engine coolant temperature above 156 °F (70 °C) Intake air temperature above 32 °F (0 °C) Vehicle speed is 0 mph (0 km/h) ST FUEL TRIM between 0.69 and 1.47 FSS is CLOSED
  13. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES -If DTC P0506 is indicated, go to step 1 and recheck. If any other temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. NO -Go to step 14.
  14. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES -Troubleshooting is complete. NO -If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, go to step 12 and recheck.
  15. Remove the intake air duct from the throttle body.
  16. Check for dirt, carbon, or damage in the throttle bore. Is there dirt, carbon, or damage in the throttle bore? YES -If there is dirt or carbon, clean the throttle body (see «THROTTLE BODY TEST»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#intake-air-system) ), and also check for damage at the air cleaner element (see «AIR CLEANER REMOVAL/INSTALLATION»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#intake-air-system) ), then go to step 9 . If there is damage in the throttle bore, go to step 8 . NO -Go to step 17.
  17. Recheck with different load conditions (turn on the headlights, blower motor, rear window defogger and/or A/C, changing the gear position, etc.).
  18. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES -Intermittent failure, system is OK at this time. NO -If the screen indicates FAILED, check the A/C system and/or power steering system, then go to step 1 and recheck. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, go to step 17 and recheck.

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

  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  4. Monitor the OBD STATUS for DTC P0507 in the DTCs MENU with the HDS. Does the screen indicate FAILED? YES -Go to step 5. NO -If the screen indicates PASSED, intermittent failure, system is OK at this time. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, recheck with different load conditions (electrical, A/C, gear position, etc.), then go to step 3.
  5. Check for vacuum leaks at these parts: PCV valve PCV hose EVAP canister purge valve Throttle body Intake manifold Brake booster hose Are there any leaks? YES -Repair or replace the leaking part(s), then go to step 6. NO -Go to step 6.
  6. Turn the ignition switch ON (II).
  7. Reset the ECM/PCM with the HDS.
  8. Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#idle-control-system__ecmpcm-idle-learn-procedure) ).
  9. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  10. Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES -If DTC P0507 is indicated, check for poor connections or loose terminals at the throttle body, the throttle actuator control module, 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. NO -Go to step 11.
  11. Monitor the OBD STATUS for DTC P0507 in the DTCs MENU with the HDS. Does the screen indicate PASSED?
  1. YES -Troubleshooting is complete.
  2. NO -If the screen indicates FAILED, check for poor connections or loose terminals at the throttle body, the throttle actuator control module, and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING, let the engine idle until a result comes on. If the screen indicates OUT OF CONDITION, recheck with different load conditions (electrical, A/C, gear position, etc.), then go to step 8.

Scheme 479

Scheme 479: A/C Signal Circuit Troubleshooting
Scheme 479: A/C Signal Circuit Troubleshooting
  1. Start the engine.
  2. Turn the blower switch on.
  3. Turn the A/C switch on.
  4. Check the A/C CLUTCH in the DATA LIST with the HDS. Does it indicate ON? YES -Go to step 5. NO -Do the A/C pressure switch circuit troubleshooting (see «A/C PRESSURE SWITCH CIRCUIT TROUBLESHOOTING»(/acura/tl/iii-2003-2006/remont/automatic-hvac-system/#climate-control-system__ac-pressure-switch-circuit-troubleshooting) ).
  5. Check the A/C system. Does the A/C system operate? YES -The air conditioning system circuit is OK. NO -Go to step 6.
  6. Turn the ignition switch OFF.
  7. Turn the ignition switch ON (II).
  8. Activate the A/C CLUTCH in the INSPECTION MENU with the HDS. Is there a clicking noise from the A/C compressor clutch? YES -Do the A/C system test (see «A/C SYSTEM TEST»(/acura/tl/iii-2003-2006/remont/automatic-hvac-system/#climate-control-system) ). NO -Go to step 9.
  9. Momentarily connect under-hood fuse/relay box 16P connector terminal No. 15 to body ground with a jumper wire several times. Is there clicking noise from the A/C compressor clutch? YES -Repair open in the wire between the ECM/PCM (A27) (2004-2005 models), (E27) (2006 model) and the A/C clutch relay. NO -Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/ PCM (see «HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ).

Scheme 480

Scheme 480: 2004-2005 models
Scheme 480: 2004-2005 models

Scheme 481

Scheme 481
Scheme 481

Scheme 482

Scheme 482
Scheme 482

Scheme 483

Scheme 483
Scheme 483
  1. Start the engine, and let it idle.
  2. Monitor the ALTERNATOR in the DATA LIST with the HDS.
  3. Check if the indicated percentage varies when the headlight switch is on. Does the percentage vary? YES -The alternator signal circuit is OK. NO -Go to step 4.
  4. Turn the headlight switch and ignition switch OFF.
  5. Disconnect the alternator 4P connector.
  6. Turn the ignition switch ON (II).
  7. Measure voltage between ECM/PCM connector terminals E3 and E12. Is there about 5 V? YES -Go to step 8. NO -Go to step 13.
  8. Turn the ignition switch OFF.
  9. Jump the SCS line with the HDS.
  10. Disconnect ECM/PCM connector E (31P).
  11. Connect alternator 4P connector terminal No. 4 to body ground with a jumper wire.
  12. Check for continuity between body ground and ECM/PCM connector terminal E12. Is there continuity? YES -Test the alternator (see «ALTERNATOR AND REGULATOR CIRCUIT TROUBLESHOOTING»(/acura/tl/iii-2003-2006/remont/charging-system/#charging-system) ). NO -Repair open in the wire between the ECM/PCM (E12) and the alternator.
  13. Turn the ignition switch OFF.
  14. Jump the SCS line with the HDS.
  15. Disconnect ECM/PCM connector E (31P).
  16. Check for continuity between body ground and ECM/PCM connector terminal E12. Is there continuity? YES -Repair short in the wire between the ECM/PCM (E12) and the alternator. NO -Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/ PCM (see «HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ).

Scheme 484

Scheme 484: 2006 model
Scheme 484: 2006 model
  1. Start the engine, and let it idle.
  2. Monitor the ALTERNATOR in the DATA LIST with the HDS.
  3. Check if the indicated percentage changes when the headlight switch is turned on. Does the percentage vary? YES -The alternator signal circuit is OK. NO -Go to step 4.
  4. Turn the headlight switch and ignition switch OFF.
  5. Jump the SCS line with the HDS.
  6. Disconnect the alternator 4P connector.
  7. Disconnect ECM/PCM connector A (31P).
  8. Check for continuity between body ground and ECM/PCM connector terminal A12. Is there continuity? YES -Repair short in the wire between the ECM/PCM (A12) and the alternator. NO -Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/ PCM (see «HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ).

Scheme 485

Scheme 485: 2004-2005 models
Scheme 485: 2004-2005 models

Scheme 486

Scheme 486
Scheme 486

Scheme 487

Scheme 487
Scheme 487

Scheme 488

Scheme 488
Scheme 488

Scheme 489

Scheme 489
Scheme 489
  1. Start the engine, and let it idle.
  2. Align the steering wheel straight ahead.
  3. Check the PSP SWITCH in the DATA LIST with the HDS. Does it indicate ON? YES -Go to step 4. NO -Go to step 14 .
  4. Turn the steering wheel to the full lock position.
  5. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to OFF? YES -The PSP switch signal circuit is OK. NO -Go to step 6.
  6. Turn the ignition switch OFF.
  7. Disconnect the PSP switch 2P connector.
  8. Start the engine.
  9. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to OFF? YES -Replace the PSP switch (see «POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT»(/acura/tl/iii-2003-2006/remont/manual-power-steering/#power-steering-system__power-steering-hose-line-and-pressure) ). NO -Go to step 10.
  10. Turn the ignition switch OFF.
  11. Jump the SCS line with the HDS.
  12. Disconnect ECM/PCM connector A (31P).
  13. Check for continuity between PSP switch 2P connector terminal No. 1 and body ground. Is there continuity? YES -Repair short in the wire between the ECM/PCM (A17) and the PSP switch. NO -Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM (see «HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ).
  14. Turn the ignition switch OFF.
  15. Disconnect the PSP switch 2P connector.
  16. Connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then start the engine.
  17. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to ON? YES -Replace the PSP switch (see «POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT»(/acura/tl/iii-2003-2006/remont/manual-power-steering/#power-steering-system__power-steering-hose-line-and-pressure) ). NO -Go to step 18.
  18. Turn the ignition switch OFF.
  19. Remove the jumper wire from the PSP switch 2P connector.
  20. Jump the SCS line with the HDS.
  21. Disconnect ECM/PCM connector A (31P).
  22. Connect PSP switch 2P connector terminal No. 1 to body ground with a jumper wire.
  23. Check for continuity between body ground and ECM/PCM connector terminal A17. Is there continuity? YES -Go to step 24. NO -Repair open in the wire between the PSP switch and the ECM/PCM (A17).
  24. Check for continuity between PSP switch 2P connector terminal No. 2 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 TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ). NO -Repair open in the wire between the PSP switch and G202.

Scheme 490

Scheme 490: 2006 model
Scheme 490: 2006 model

Scheme 491

Scheme 491
Scheme 491

Scheme 492

Scheme 492
Scheme 492

Scheme 493

Scheme 493
Scheme 493

Scheme 494

Scheme 494
Scheme 494
  1. Start the engine, and let it idle.
  2. Align the steering wheel straight ahead.
  3. Check the PSP SWITCH in the DATA LIST with the HDS. Does it indicate ON? YES -Go to step 4. NO -Go to step 14 .
  4. Turn the steering wheel to the full lock position.
  5. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to OFF? YES -The PSP switch signal circuit is OK. NO -Go to step 6.
  6. Turn the ignition switch OFF.
  7. Disconnect the PSP switch 2P connector.
  8. Start the engine.
  9. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to OFF? YES -Replace the PSP switch (see «POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT»(/acura/tl/iii-2003-2006/remont/manual-power-steering/#power-steering-system__power-steering-hose-line-and-pressure) ). NO -Go to step 10.
  10. Turn the ignition switch OFF.
  11. Jump the SCS line with the HDS.
  12. Disconnect ECM/PCM connector E (31P).
  13. Check for continuity between PSP switch 2P connector terminal No. 1 and body ground. Is there continuity? YES -Repair short in the wire between the ECM/PCM (E17) and the PSP switch. NO -Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/ PCM (see «HOW TO TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ).
  14. Turn the ignition switch OFF.
  15. Disconnect the PSP switch 2P connector.
  16. Connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then start the engine.
  17. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to ON? YES -Replace the PSP switch (see «POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT»(/acura/tl/iii-2003-2006/remont/manual-power-steering/#power-steering-system__power-steering-hose-line-and-pressure) ). NO -Go to step 18.
  18. Turn the ignition switch OFF.
  19. Remove the jumper wire from the PSP switch 2P connector.
  20. Jump the SCS line with the HDS.
  21. Disconnect ECM/PCM connector E (31P).
  22. Connect PSP switch 2P connector terminal No. 1 to body ground with a jumper wire.
  23. Check for continuity between body ground and ECM/PCM connector terminal E17. Is there continuity? YES -Go to step 24. NO -Repair open in the wire between the PSP switch and the ECM/PCM (E17).
  24. Check for continuity between PSP switch 2P connector terminal No. 2 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 TROUBLESHOOT CIRCUITS AT THE ECM/PCM»(/acura/tl/iii-2003-2006/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__how-to-troubleshoot-circuits-at-the) ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#pgm-fi-system) ). NO -Repair open in the wire between the PSP switch and G202.

Scheme 495

Scheme 495: 2004-2005 models
Scheme 495: 2004-2005 models

Scheme 496

Scheme 496
Scheme 496
  1. Turn the ignition switch ON (II).
  2. Check the BRAKE SWITCH in the DATA LIST with the HDS. Does it indicate OFF? YES -Go to step 3. NO -Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/tl/iii-2003-2006/remont/mechanical-hydraulic/#conventional-brake-components) ).
  3. Press the brake pedal, and check the BRAKE SWITCH in the DATA LIST with the HDS. Does it change to ON? YES -The brake pedal position switch signal circuit (BKSW line) is OK. NO -Go to step 4.
  4. Turn the ignition switch OFF.
  5. Jump the SCS line with the HDS.
  6. Disconnect the brake pedal position switch 4P connector.
  7. Disconnect ECM/PCM connector A (31P).
  8. Check for continuity between ECM/PCM connector terminal A8 and body ground. Is there continuity? YES -Repair short in the wire between the ECM/PCM (A8) and the No. 13 HORN, STOP (20 A) fuse. Replace the No. 13 HORN, STOP (20 A) fuse. NO -Go to step 9.
  9. Check for continuity between ECM/PCM connector terminal A8 and brake pedal position switch 4P connector terminal No. 2. Is there continuity? YES -Repair open in the wire between the brake pedal position switch and the No. 13 HORN, STOP (20 A) fuse. Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/tl/iii-2003-2006/remont/mechanical-hydraulic/#conventional-brake-components) ). NO -Repair open in the wire between the ECM/PCM (A8) and the brake pedal position switch.

Scheme 497

Scheme 497: 2006 model
Scheme 497: 2006 model

Scheme 498

Scheme 498
Scheme 498
  1. Turn the ignition switch ON (II).
  2. Check the BRAKE SWITCH in the DATA LIST with the HDS. Does it indicate OFF? YES -Go to step 3. NO -Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/tl/iii-2003-2006/remont/mechanical-hydraulic/#conventional-brake-components) ).
  3. Press the brake pedal, and check the BRAKE SWITCH in the DATA LIST with the HDS. Does it change to ON? YES -The brake pedal position switch signal circuit (BKSW line) is OK. NO -Go to step 4.
  4. Turn the ignition switch OFF.
  5. Jump the SCS line with the HDS.
  6. Disconnect the brake pedal position switch 4P connector.
  7. Disconnect ECM/PCM connector E (31P).
  8. Check for continuity between ECM/PCM connector terminal E8 and body ground. Is there continuity? YES -Repair short in the wire between the ECM/PCM (E8) and the No. 13 HORN, STOP (20 A) fuse. Replace the No. 13 HORN, STOP (20 A) fuse. NO -Go to step 9.
  9. Check for continuity between ECM/PCM connector terminal E8 and brake pedal position switch 4P connector terminal No. 2. Is there continuity? YES -Repair open in the wire between the brake pedal position switch and the No. 13 HORN, STOP (20 A) fuse. Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/tl/iii-2003-2006/remont/mechanical-hydraulic/#conventional-brake-components) ). NO -Repair open in the wire between the ECM/PCM (E8) and the brake pedal position switch.

Idle Speed Inspection

Note. Before checking the idle speed, check these items: The malfunction indicator lamp (MIL) has not been reported on and there are no DTCs. Ignition timing Spark plugs Air cleaner PCV system Apply the parking brake.

Scheme 499

Scheme 499: Idle Speed Inspection
Scheme 499: Idle Speed Inspection
  1. Disconnect evaporative emission (EVAP) canister purge valve connector.
  2. Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
  3. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
  4. Check the idle speed without load conditions: headlights, blower fan, radiator fan, and air conditioner off. Idle speed should be: 750+/-50 RPM (in Park or neutral)
  5. Let the engine idle for 1 minute with high electric load (A/C switch ON, temperature set to MAX Cool, blower fan on High, rear window defogger ON, and headlights on high beam). Idle speed should be: 750+/-50 RPM (in Park or neutral) NOTE: If the idle speed is not within specification, do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(/acura/tl/iii-2003-2006/remont/testing-diagnostics/#idle-control-system__ecmpcm-idle-learn-procedure) ). If no change in idle speed, go to symptom troubleshooting.
  6. Reconnect the EVAP canister purge valve connector.

ECM/PCM Idle Learn Procedure

The idle learn procedure must be done so the ECM/PCM can learn the engine idle characteristics.

Do the idle learn procedure whenever you do any of these procedures

  1. Replace the throttle body
  2. Clean the throttle body
  3. Replace ECM/PCM
  4. Update ECM/PCM
  5. Reset ECM/PCM

Note. Erasing DTCs with the HDS does not require you to do the idle learn procedure.

Procedure

  1. Make sure all electrical items (A/C, audio, rear window defogger, lights, etc.) are off.
  2. Reset the ECM/PCM with the HDS.
  3. Turn the ignition switch ON (II), and wait 2 seconds.
  4. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, or until the engine coolant temperature reaches 194 °F (90 °C).
  5. Let the engine idle for about 5 minutes with the throttle fully closed. NOTE: If the radiator fan comes on, do not include its running time in the 5 minutes.

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