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Idle Control System Acura TL IV

Testing & Diagnostics 7 illustrations ~2347 words

Scheme 27

Scheme 27: Component Location Index
Scheme 27: 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 to ON (II), or press the engine start/stop button to select the ON mode
  2. Clear the DTC with the HDS
  3. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle for 20 seconds or more
  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 15 If the screen indicates EXECUTING, keep idling 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/tl/iv-2008-2011/remont/testing-diagnostics/#intake-air-system__throttle-body-cleaning) ) Also check for damage to the air cleaner element (see «AIR CLEANER ELEMENT INSPECTION/REPLACEMENT»(/acura/tl/iv-2008-2011/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 the power steering system, then go to step 17
  8. Replace the throttle body (see «THROTTLE BODY REMOVAL/INSTALLATION»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#intake-air-system__throttle-body-removalinstallation) )
  9. Reset the PCM with the HDS
  10. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
  11. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle for 20 seconds or more
  12. 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
  13. Check for Pending or Confirmed DTCs with the HDS Is DTC P0506 indicated? YES -Go to step 1 and recheck 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 If any other Pending or Confirmed DTCs were indicated in step 13, go to the indicated DTC's troubleshooting NO -If the screen indicates FAILED, check the A/C system and/or the power steering system, then go to step 1 If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION, go to step 12
  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 CLEANING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#intake-air-system__throttle-body-cleaning) ) Also check for damage to the air cleaner element (see «AIR CLEANER ELEMENT INSPECTION/REPLACEMENT»(/acura/tl/iv-2008-2011/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, the rear window defogger and/or the A/C, change 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, the system is OK at this time NO -If the screen indicates FAILED, check the A/C system and/or the power steering system, then go to step 1 If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION, go to step 12

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 to ON (II), or press the engine start/stop button to select the ON mode
  2. Clear the DTC with the HDS
  3. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in 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, keep idling 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 Brake booster 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 to ON (II), or press the engine start/stop button to select the ON mode
  7. Reset the PCM with the HDS
  8. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
  9. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle
  10. Check for Pending or Confirmed DTCs with the HDS Is DTC P0507 indicated? YES -Check for poor connections or loose terminals at the throttle body and the PCM, then 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 -Troubleshooting is complete If any other Pending or Confirmed DTCs were indicated in step 10, go to the indicated DTC's troubleshooting NO -If the screen indicates FAILED, check for poor connections or loose terminals at the throttle body and the PCM, then go to step 1 If the screen indicates EXECUTING, keep idling until a result comes on If the screen indicates OUT OF CONDITION, recheck with different load conditions (turn on the headlights, the blower motor, or the A/C, change the gear position, etc), then go to step 9

Scheme 28

Scheme 28: A/C Signal Circuit Troubleshooting
Scheme 28: 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 -Check the A/C system (see «A/C SYSTEM INSPECTION»(/acura/tl/iv-2008-2011/remont/automatic-hvac-system/#climate-control-system__ac-system-inspection) )
  5. Check the A/C system operation Does the A/C system operate? YES -The air conditioning system circuit is OK NO -Go to step 6
  6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
  7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  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/iv-2008-2011/remont/automatic-hvac-system/#climate-control-system) ) NO -Go to step 9
  9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
  10. Jump the SCS line with the HDS
  11. Disconnect PCM connector A (49P)
  12. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  13. Momentarily connect PCM connector terminal A13 to body ground with a jumper wire several times Is there a clicking noise from the A/C compressor clutch? YES -Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) NO -Check for poor connections or loose terminals at the A/C clutch relay and the PCM If the connections are OK, check the A/C clutch relay (see «POWER RELAY TEST»(/acura/tl/iv-2008-2011/remont/body-electrical/#relays__power-relay-test) ) If needed, repair open in the wire between the PCM (A13), the A/C clutch relay, and the other A/C system parts

Scheme 29

Scheme 29: Alternator FR Signal Circuit Troubleshooting
Scheme 29: 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 varies 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 off, and turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
  5. Jump the SCS line with the HDS
  6. Disconnect the alternator 4P connector
  7. Disconnect PCM connector C (49P)
  8. Check for continuity between PCM connector terminal C44 and body ground Is there continuity? YES -Repair short in the wire between the PCM (C44) and the alternator NO -Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the symptom/indication goes away with a known-good PCM, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) )

Scheme 30

Scheme 30: Brake Pedal Position Switch Signal Circuit Troubleshooting
Scheme 30: Brake Pedal Position Switch Signal Circuit Troubleshooting

Scheme 31

Scheme 31
Scheme 31

Scheme 32

Scheme 32
Scheme 32
  1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  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/iv-2008-2011/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 to LOCK (0), or press the engine start/stop button to select the OFF mode
  5. Jump the SCS line with the HDS
  6. Disconnect the brake pedal position switch 4P connector
  7. Disconnect PCM connector A (49P)
  8. Check for continuity between PCM connector terminal A8 and body ground Is there continuity? YES -Repair short in the wire between the PCM (A8) and the brake pedal position switch Also replace the No 10 HORN/STOP (20 A) fuse in the under-hood fuse/relay box NO -Go to step 9
  9. Connect brake pedal position switch 4P connector terminal No 2 to body ground with a jumper wire
  10. Check for continuity between PCM connector terminal A8 and body ground Is there continuity? YES -Repair open in the wire between the brake pedal position switch, and also replace the No 10 HORN/STOP (20 A) fuse in the under-hood fuse/relay box Inspect the brake pedal position switch (see «BRAKE PEDAL AND BRAKE PEDAL POSITION SWITCH ADJUSTMENT»(/acura/tl/iv-2008-2011/remont/mechanical-hydraulic/#conventional-brake-components) ) NO -Repair open in the wire between the PCM (A8) 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, and make sure the headlights are off

Scheme 33

Scheme 33: Idle Speed Inspection
Scheme 33: 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. Make sure the HDS communicates with the PCM If it doesn't, go to the DLC circuit troubleshooting (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) )
  4. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle
  5. Check the idle speed without load conditions headlights, blower fan, radiator fan, and air conditioner off Idle speed should be: IDLE SPEED CHART J35Z6 engine 680 ± 50 rpm in (P or N) J37A4 (M/T) 750 ± 50 rpm (in neutral) J37A4 engine 700 ± 50 rpm in (P or N)
  6. Let the engine idle for 1 minute with high electric load (the A/C switch on, the temperature set to max cool, the blower fan on high, and the headlights on high beam) Idle speed should be. IDLE SPEED CHART J35Z6 engine 680 ± 50 rpm in (P or N) J37A4 (M/T) 750 ± 50 rpm (in neutral) J37A4 engine 700 ± 50 rpm in (P or N) NOTE: If the idle speed is not within specification, do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) ) If the idle speed is still not within specification, go to the symptom troubleshooting
  7. Reconnect the EVAP canister purge valve connector

PCM Idle Learn Procedure

The idle learn procedure must be done so the PCM can learn 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
  5. Disassemble the engine or transmission

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

Procedure

  1. Make sure all electrical items (the A/C, the audio, the lights, etc) are off
  2. Reset the PCM with the HDS
  3. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and wait 2 seconds
  4. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, or until the engine coolant temperature reaches 194 T (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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