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Engine Control System (Service Information): Overview Lexus GS III facelift

Engine Control Systems 18 illustrations ~1090 words

Scheme 3

Scheme 3: ILLUSTRATION
Scheme 3: ILLUSTRATION

Scheme 4

Scheme 4: ON-VEHICLE INSPECTION
Scheme 4: ON-VEHICLE INSPECTION
  1. CHECK THROTTLE BODY Check the throttle control motor operating sounds. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the ETCS Open Slow Speed, Control the ETCS Close Slow Speed, Control the ETCS Open Fast Speed and Control the ETCS Close Fast Speed. Check the operating sound of the running motor. Make sure that no friction noises emit from the motor. If a friction noise exists, replace the throttle body. Check the throttle position sensor. Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the ETCS Open Slow Speed, Control the ETCS Close Slow Speed, Control the ETCS Open Fast Speed and Control the ETCS Close Fast Speed. Specified Condition Tester Display Specified Condition Throttle position Value varies according to Active Test Throttle Sensor position Throttle Sensor position #2 If the result is not as specified, replace the throttle body.

Scheme 5

Scheme 5: REMOVAL
Scheme 5: REMOVAL

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

Scheme 9

Scheme 9
Scheme 9
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE COOL AIR INTAKE DUCT SEAL. Refer to «REMOVAL - Step 15»(ref-382704-S06161003072011012800000)
  3. DRAIN ENGINE COOLANT. Refer to «REPLACEMENT - Step 5»(ref-382708-S21361285702011012800000)
  4. REMOVE ENGINE ROOM SIDE COVER RH. Refer to «REMOVAL - Step 16»(ref-382704-S06161003072011012800000)
  5. REMOVE V-BANK COVER. Refer to «REMOVAL - Step 18»(ref-382704-S06161003072011012800000)
  6. REMOVE NO. 1 AIR CLEANER INLET. Refer to «REMOVAL - Step 19»(ref-382704-S06161003072011012800000)
  7. DISCONNECT NO. 2 VENTILATION HOSE Disconnect the ventilation hose from the cylinder head.
  8. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE Disconnect the MAF meter connector. Disconnect the clamp from the air cleaner cap. Disconnect the purge line hose. Disconnect the 4 clamps. Remove the hose clamp and air cleaner cap with air cleaner hose.
  9. REMOVE THROTTLE BODY Disconnect the throttle motor connector. Remove the 4 bolts and disconnect the throttle body from the intake air surge tank. Disconnect the 2 water by-pass hoses from the throttle body. Remove the throttle body and gasket.

Scheme 10

Scheme 10: INSPECTION
Scheme 10: INSPECTION
  1. INSPECT THROTTLE BODY Measure the resistance between the terminals. Standard resistance Tester Connection Condition Specified Condition 1 (M-) - 2 (M+) 20°C (68°F) 0.3 to 100 ohms 3 (E2) - 5 (VC) 20°C (68°F) 1.2 to 3.2 kohms If the result is not as specified, replace the throttle body.

Scheme 11

Scheme 11: INSTALLATION
Scheme 11: INSTALLATION
  1. INSTALL THROTTLE BODY Install a new gasket to the intake air surge tank. HINT: Align the protrusion of the gasket on the intake air surge tank. Connect the 2 water by-pass hoses to the throttle body. Install the throttle body with the 4 bolts. Torque: 10 N*m ( 102 kgf*cm, 7 ft.*lbf) Connect the throttle motor connector.
  2. INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE Install the air cleaner cap with air cleaner hose assembly with the 4 clamps and hose clamp. Torque: 4.0 N*m ( 41 kgf*cm, 35 in.*lbf) for hose clamp HINT: Fit the protrusion on the air cleaner hose into the hole of the hose clamp on the throttle valve side. Connect the purge line hose to the air cleaner hose. Connect the MAF meter connector and clamp to the air cleaner cap.
  3. CONNECT NO. 2 VENTILATION HOSE Connect the ventilation hose to the cylinder head cover with the clamp.
  4. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
  5. ADD ENGINE COOLANT. Refer to «REPLACEMENT - Step 6»(ref-382708-S21361285702011012800000)
  6. INSPECT FOR COOLANT LEAK . Refer to «ON-VEHICLE INSPECTION - Step 3»(/lexus/gs/iii-facelift-2007-2011/remont/cooling-system-mechanical/#cooling-inspection)
  7. INSPECT FUNCTION OF THROTTLE BODY See step 1
  8. INSTALL NO. 1 AIR CLEANER INLET. Refer to «INSTALLATION - Step 114»(ref-382704-S21777018532011012800000)
  9. INSTALL V-BANK COVER. Refer to «INSTALLATION - Step 132»(ref-382704-S21777018532011012800000)
  10. INSTALL ENGINE ROOM SIDE COVER RH. Refer to «INSTALLATION - Step 134»(ref-382704-S21777018532011012800000)
  11. INSTALL COOL AIR INTAKE DUCT SEAL. Refer to «INSTALLATION - Step 135»(ref-382704-S21777018532011012800000)
  12. PERFORM INITIALIZATION Perform initialization Refer to «INITIALIZATION»(ref-382578-S40254115562011012800000). NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.

Scheme 12

Scheme 12: ILLUSTRATION
Scheme 12: ILLUSTRATION

Scheme 13

Scheme 13: REMOVAL
Scheme 13: REMOVAL

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15
Scheme 15
  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to prevent airbag and seat belt pretensioner activation.
  2. REMOVE COOL AIR INTAKE DUCT SEAL. Refer to «REMOVAL - Step 15»(ref-382704-S06161003072011012800000)
  3. REMOVE ENGINE ROOM SIDE COVER LH. Refer to «REMOVAL - Step 17»(ref-382704-S06161003072011012800000)
  4. REMOVE ECM BOX COVER NOTE: Remove all water on and around the cover. Perform the inspection indoors to avoid rain. Be sure to prevent water intrusion to the ECM (connectors and screw parts). Remove the 3 bolts and cover.
  5. DISCONNECT WIRE HARNESS Using a screw driver, detach the 2 claws. HINT: Tape the screwdriver tip before use. Disconnect the 2 connector holders. Disconnect the 6 connectors.
  6. REMOVE ECM Remove the 2 nuts and ECM.

Scheme 16

Scheme 16: INSTALLATION
Scheme 16: INSTALLATION

Scheme 17

Scheme 17
Scheme 17

Scheme 18

Scheme 18
Scheme 18
  1. INSTALL ECM NOTE: Install the ECM in the ECM box with the name plate facing the inside of the vehicle. Make sure that there is no foreign matter on the gasket surface of the ECM box. Insert the stud bolt in the vehicle rear side to the ECM first. Make sure that the stud bolts are securely installed into the front and rear bolt holes. Install the ECM to the ECM box. NOTE: Be sure to first tighten the nut on the vehicle rear. Install the 2 nuts in the order shown in the illustration. Torque: 5.5 N*m ( 56 kgf*cm, 49 in.*lbf)
  2. CONNECT WIRE HARNESS Attach the 2 claws. Connect the 2 connector holders. Connect the 6 connectors.
  3. INSTALL ECM BOX COVER NOTE: Make sure that the wire harness does not get caught between the parts. Install the cover with the 3 bolts. Torque: 5.5 N*m ( 56 kgf*cm, 49 in.*lbf)
  4. INSTALL ENGINE ROOM SIDE COVER LH. Refer to «INSTALLATION - Step 133»(ref-382704-S21777018532011012800000)
  5. INSTALL COOL AIR INTAKE DUCT SEAL. Refer to «INSTALLATION - Step 135»(ref-382704-S21777018532011012800000)
  6. CONNECT CABLE TO NEGATIVE BATTERY TERMINAL
  7. PERFORM REGISTRATION Perform registration Refer to «PRECAUTION»(ref-382723-S23728041952011012800000).
  8. RESET MEMORY Reset memory for 2WD Refer to «INITIALIZATION»(ref-382733-S10012586692011012800000). Reset memory for 4WD Refer to «INITIALIZATION»(ref-382734-S18013438302011012800000).
  9. PERFORM INITIALIZATION Perform initialization Refer to «INITIALIZATION»(ref-382578-S40254115562011012800000). NOTE: Certain systems need to be initialized after disconnecting and reconnecting the cable from the negative (-) battery terminal.

Scheme 19

Scheme 19: ILLUSTRATION
Scheme 19: ILLUSTRATION

Scheme 20

Scheme 20: ILLUSTRATION
Scheme 20: ILLUSTRATION

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