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Idle Control System Acura RL II

Engine Control Systems 11 illustrations ~2681 words

Scheme 1

Scheme 1: Component Location Index
Scheme 1: Component Location Index

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: ECT SENSOR 1 above 158°F (70°C) IAT SENSOR above 32°F (0°C) VSS is 0 mph (0 km/h) ST FUEL TRIM between 0.73 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 8 . 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 CLEANING»(/acura/rl/ii-2004-2008/remont/mechanical/#intake-air-system__throttle-body-cleaning) ). Also check for damage to the air cleaner element (see «AIR CLEANER ELEMENT INSPECTION/REPLACEMENT»(/acura/rl/ii-2004-2008/remont/mechanical/#intake-air-system) ), then go to step 13 . If there is damage in the throttle bore, go to step 12 . NO - Check the A/C system or power steering system, then go to step 10 .
  8. Remove the intake air duct from the throttle body.
  9. 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 CLEANING»(/acura/rl/ii-2004-2008/remont/mechanical/#intake-air-system__throttle-body-cleaning) ). Also check for damage to the air cleaner element (see «AIR CLEANER ELEMENT INSPECTION/REPLACEMENT»(/acura/rl/ii-2004-2008/remont/mechanical/#intake-air-system) ), then go to step 13 . If there is damage in the throttle bore, go to step 12 . NO - Go to step 10.
  10. Recheck with different load conditions (turn on the headlights, blower motor, or A/C; change the gear position, etc.).
  11. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES - Intermittent failure, the 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 10 and recheck.
  12. Replace the throttle body (see «THROTTLE BODY REMOVAL/INSTALLATION»(/acura/rl/ii-2004-2008/remont/mechanical/#intake-air-system__throttle-body-removalinstallation) ).
  13. Reset the PCM with the HDS.
  14. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rl/ii-2004-2008/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ).
  15. 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.
  16. Check for these conditions in the DATA LIST with the HDS: ECT SENSOR 1 above 158°F (70°C) IAT SENSOR above 32°F (0°C) VSS is 0 mph (0 km/h) ST FUEL TRIM between 0.73 and 1.47 FSS is CLOSED
  17. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0506 indicated? YES - Check for poor connections or loose terminals at the throttle body and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the PCM was substituted, go to step 1 . NO - Go to step 18.
  18. Monitor the OBD STATUS for DTC P0506 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). If any other Temporary DTCs or DTCs were indicated in step 17 , go to the indicated DTCs troubleshooting. NO - If the screen indicates FAILED, check for poor connections or loose terminals at the throttle body and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the PCM was substituted, go to step 1 . If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.

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, the 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 PCM with the HDS.
  8. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rl/ii-2004-2008/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ).
  9. Start the engine. Hold the engine speed at 3,000 RPM without load (in Park of neutral) until the radiator fan comes on, then let it idle.
  10. Check for Temporary DTCs or DTCs with the HDS. Is DTC P0507 indicated? YES - Check for poor connections or loose terminals at the throttle body, the throttle actuator control module, and the PCM. If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the PCM was substituted, go to step 1 . 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? YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see «PCM REPLACEMENT»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). If any other Temporary DTCs or DTCs were indicated in step 10 , go to the indicated DTCs troubleshooting. NO - If the screen indicates FAILED, check for poor connections or loose terminals at the throttle body, the throttle actuator control module, and the PCM. If the PCM was updated/substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the PCM was substituted, go to step 1 . If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.

Scheme 2

Scheme 2: A/C Signal Circuit Troubleshooting
Scheme 2: 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. Is it ON? YES - Go to step 5. NO - Go to the A/C pressure switch circuit troubleshooting (see «DTC B2979 OR PRE SENSOR OPEN IS INDICATED: AN OPEN IN THE A/C PRESSURE SENSOR CIRCUIT»(/acura/rl/ii-2004-2008/remont/automatic-hvac-system/#hvac) ).
  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/rl/ii-2004-2008/remont/automatic-hvac-system/#hvac) ). 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 PCM (E27) and the A/C clutch relay. NO - Update the PCM if it does not have the latest software (see «UPDATING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__updating-the-pcm) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ).

Scheme 3

Scheme 3: Alternator FR Signal Circuit Troubleshooting
Scheme 3: Alternator FR Signal Circuit Troubleshooting
  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 PCM connector A (31P).
  8. Check for continuity between body ground and PCM connector terminal A12. Is there continuity? YES - Repair short in the wire between the PCM (A12) and the alternator. NO - Update the PCM if it does not have the latest software (see «UPDATING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__updating-the-pcm) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «PCM REPLACEMENT»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).

Scheme 4

Scheme 4: PSP Switch Signal Circuit Troubleshooting
Scheme 4: PSP Switch Signal Circuit Troubleshooting

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8
  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 12 .
  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. Disconnect the PSP switch 2P connector.
  7. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to OFF? YES - Replace the PSP switch. NO - Go to step 8.
  8. Turn the ignition switch OFF.
  9. Jump the SCS line with the HDS.
  10. Disconnect PCM connector E (31P).
  11. 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 PCM (E17) and the PSP switch. NO - Update the PCM if it does not have the latest software (see «UPDATING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__updating-the-pcm) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «PCM REPLACEMENT»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ).
  12. Turn the ignition switch OFF.
  13. Disconnect the PSP switch 2P connector.
  14. Connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then start the engine.
  15. Check the PSP SWITCH in the DATA LIST with the HDS. Does it change to ON? YES - Replace the PSP switch. NO - Go to step 16.
  16. Turn the ignition switch OFF.
  17. Remove the jumper wire from the PSP switch 2P connector.
  18. Jump the SCS line with the HDS.
  19. Disconnect PCM connector E (31P).
  20. Connect PSP switch 2P connector terminal No. 1 to body ground with a jumper wire.
  21. Check for continuity between body ground and PCM connector terminal E17. Is there continuity? YES - Go to step 22. NO - Repair open in the wire between the PSP switch and the PCM (E17).
  22. Check for continuity between PSP switch 2P connector terminal No. 2 and body ground. Is there continuity? YES - Update the PCM if it does not have the latest software (see «UPDATING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__updating-the-pcm) ), or substitute a known-good PCM (see «SUBSTITUTING THE PCM»(/acura/rl/ii-2004-2008/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-pcm) ), then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «PCM REPLACEMENT»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system__pcm-replacement) ). NO - Repair open in the wire between the PSP switch and G201.

Scheme 9

Scheme 9: Brake Pedal Position Switch Signal Circuit Troubleshooting
Scheme 9: Brake Pedal Position Switch Signal Circuit Troubleshooting

Scheme 10

Scheme 10
Scheme 10
  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/rl/ii-2004-2008/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 PCM connector E (31P).
  8. Check for continuity between PCM connector terminal E8 and body ground. Is there continuity? YES - Repair short in the wire between the PCM (E8) and the No. 13 HORN, STOP (15 A) fuse. Replace the No. 13 HORN, STOP (15 A) fuse. NO - Go to step 9.
  9. Check for continuity between 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 (15A) fuse. Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/rl/ii-2004-2008/remont/mechanical-hydraulic/#conventional-brake-components) ). NO - Repair open in the wire between the 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. Ignition timing Spark plugs - Air cleaner PCV system Apply the parking brake.

Scheme 11

Scheme 11: Idle Speed Inspection
Scheme 11: Idle Speed Inspection
  1. Disconnect the 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. Turn the ignition switch ON (II).
  4. Make sure the HDS communicates with the PCM and other vehicle systems. If it does not, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/rl/ii-2004-2008/remont/testing-diagnostics/#pgm-fi-system) ).
  5. 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.
  6. Check the idle speed without load conditions: headlights, blower fan, radiator fan, and air conditioner off. Idle speed should be: 680 ± 50 RPM (in Park or neutral)
  7. Let the engine idle 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: 680 ± 50 RPM (in Park or neutral) NOTE: If the idle speed is not within specification, do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/rl/ii-2004-2008/remont/engine-control-systems/#idle-control-system__pcm-idle-learn-procedure) ). If the idle speed is still not within specification, go to symptom troubleshooting.
  8. Reconnect the EVAP canister purge valve connector.

PCM Idle Learn Procedure

The PCM actively learns the idle characteristics whenever the engine is idling. The idle learn procedure must be done to ensure the PCM learns the engine idle characteristics.

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

  1. Replace the PCM.
  2. Reset the PCM.
  3. Update the PCM.
  4. Replace or clean the throttle body.

Note. Clearing the 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 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 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.
  6. Verify on the HDS data list that the idle learn procedure is complete.

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