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Engine Control (Service Information): Diagnosis Lexus RX III

Engine Control Systems 13 illustrations ~1625 words

ON-VEHICLE INSPECTION

  1. INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Connect the Techstream to the DLC3. Start the engine. Turn the Techstream on. Inspect the oil control valve (for intake camshaft). Enter the following menus: Powertrain / Engine / Active Test / Control the VVT System (Bank 1). Operate the oil control valve using the Techstream, and then check the engine speed. Standard Condition Control Range Specified Condition OCV is OFF Normal engine speed OCV is ON Soon after OCV switched from OFF to ON, engine idles roughly or stalls If the result is not as specified, check the oil control valve, wire harness and ECM. Enter the following menus: Powertrain / Engine / Active Test / Control the VVT System (Bank 2). Operate the oil control valve using the Techstream, and then check the engine speed. Standard Condition Control Range Specified Condition OCV is OFF Normal engine speed OCV is ON Soon after OCV switched from OFF to ON, engine idles roughly or stalls If the result is not as specified, check the oil control valve, wire harness and ECM. Inspect the oil control valve (for exhaust camshaft). Enter the following menus: Powertrain / Engine / Active Test / Control the VVT Exhaust Linear (Bank 1). Operate the oil control valve using the Techstream, and then check the engine speed. Standard Condition Control Range Specified Condition -100% Normal engine speed 100% Soon after OCV switched from OFF (- 100%) to ON (+100%), engine idles roughly or stalls. If the result is not as specified, check the oil control valve, wire harness and ECM. Enter the following menus: Powertrain / Engine / Active Test / Control the VVT Exhaust Linear (Bank 2). Operate the oil control valve using the Techstream, and then check the engine speed. Standard Condition Control Range Specified Condition -100% Normal engine speed 100% Soon after OCV switched from OFF (- 100%) to ON (+100%), engine idles roughly or stalls. If the result is not as specified, check the oil control valve, wire harness and ECM.

Scheme 5

Scheme 5: REMOVAL
Scheme 5: REMOVAL

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7
  1. PRECAUTION (w/ Air Suspension) NOTE: Be sure to read Precaution thoroughly before servicing. Refer to «PRECAUTION»(ref-400808-S18187891512011051800000) .
  2. PRECAUTION (w/ Navigation System for HDD) NOTE: After the engine switch is turned off, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the engine switch off, make sure to wait at least 60 seconds before disconnecting the cable from the negative (-) battery terminal.
  3. REMOVE WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY Remove the windshield wiper motor and link assembly. Refer to «REMOVAL»(ref-400809-S41356394852011051800000) .
  4. REMOVE NO. 1 ENGINE UNDER COVER
  5. DRAIN ENGINE COOLANT . Refer to «REPLACEMENT - Step 7»(ref-400800-S21803137222011051800000)
  6. REMOVE FRONT SHOCK ABSORBER CAP (w/ Air Suspension) . Refer to «REMOVAL - Step 3»(ref-400810-S01269755922011051800000)
  7. REMOVE OUTER COWL TOP PANEL SUB-ASSEMBLY . Refer to «REMOVAL - Step 11»(ref-400778-S07130150422011051800000)
  8. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL - Step 34»(ref-400790-S03510589702011051800000)
  9. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system. Refer to «PRECAUTION»(ref-400811-S16232838532011051800000) . NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to «INITIALIZATION»(ref-400649-S12881576452011051800000) .
  10. REMOVE BATTERY . Refer to «REMOVAL - Step 37»(ref-400790-S03510589702011051800000)
  11. REMOVE NO. 2 AIR CLEANER INLET . Refer to «REMOVAL - Step 35»(ref-400790-S03510589702011051800000)
  12. REMOVE NO. 1 AIR CLEANER INLET . Refer to «REMOVAL - Step 36»(ref-400790-S03510589702011051800000)
  13. REMOVE AIR CLEANER ASSEMBLY See step 13
  14. REMOVE INTAKE AIR SURGE TANK ASSEMBLY . Refer to «REMOVAL - Step 3»(ref-400802-S06641726382011051800000)
  15. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Remove the bolt and disconnect the wire harness clamp to separate the engine wire. Disconnect the 4 oil control valve connectors. Remove the 4 bolts and 4 oil control valves. Remove the O-ring from each oil control valve. TEXT IN ILLUSTRATION *1 O-ring
  1. CHECK THROTTLE BODY Check the throttle control motor operating sound. Turn the engine switch on (IG). When depressing the accelerator pedal, check the operating sound of the motor. Make sure that no friction noises are from the motor. If 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. Enter the following menus: Powertrain / Engine / Data List / Throttle Sensor Position. Depress the accelerator pedal. When the throttle valve is fully open, check that the Throttle Sensor Position value is within the specification. Standard Throttle Valve Opening Percentage Tester Display Specified Condition Throttle Sensor Position 60% or more NOTE: When checking the throttle valve opening percentage, the shift lever should be in N. Fully depress the accelerator pedal. If the percentage is less than 60%, replace the throttle body.

Scheme 8

Scheme 8: REMOVAL
Scheme 8: REMOVAL

Scheme 9

Scheme 9
Scheme 9

Scheme 10

Scheme 10
Scheme 10

Scheme 11

Scheme 11
Scheme 11

Scheme 12

Scheme 12
Scheme 12

Scheme 13

Scheme 13
Scheme 13

Scheme 14

Scheme 14
Scheme 14

Scheme 15

Scheme 15
Scheme 15
  1. PRECAUTION (w/ Air Suspension) NOTE: Be sure to read Precaution thoroughly before servicing. Refer to «PRECAUTION»(ref-400808-S18187891512011051800000) .
  2. PRECAUTION (w/ Navigation System for HDD) NOTE: After the engine switch is turned off, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the engine switch off, make sure to wait at least 60 seconds before disconnecting the cable from the negative (-) battery terminal.
  3. REMOVE WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY Remove the windshield wiper motor and link assembly. Refer to «REMOVAL»(ref-400809-S41356394852011051800000) .
  4. REMOVE FRONT SHOCK ABSORBER CAP (w/ Air Suspension) . Refer to «REMOVAL - Step 3»(ref-400810-S01269755922011051800000)
  5. REMOVE OUTER COWL TOP PANEL SUB-ASSEMBLY . Refer to «REMOVAL - Step 11»(ref-400778-S07130150422011051800000)
  6. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL - Step 34»(ref-400790-S03510589702011051800000)
  7. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL WARNING: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system. Refer to «PRECAUTION»(ref-400811-S16232838532011051800000) . NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to «INITIALIZATION»(ref-400649-S12881576452011051800000) .
  8. REMOVE NO. 1 ENGINE UNDER COVER
  9. DRAIN ENGINE COOLANT . Refer to «REPLACEMENT - Step 7»(ref-400800-S21803137222011051800000)
  10. REMOVE NO. 2 AIR CLEANER INLET . Refer to «REMOVAL - Step 35»(ref-400790-S03510589702011051800000)
  11. REMOVE NO. 1 AIR CLEANER INLET . Refer to «REMOVAL - Step 36»(ref-400790-S03510589702011051800000)
  12. REMOVE BATTERY . Refer to «REMOVAL - Step 37»(ref-400790-S03510589702011051800000)
  13. REMOVE AIR CLEANER ASSEMBLY Separate the mass air flow meter connector and wire harness clamp. Separate the vacuum hose from the intake air surge tank assembly. Separate the vacuum hose from the hose clamp. Separate the vacuum switching valve connector and 2 wire harness clamps. Separate the 2 vacuum hoses. Separate the ventilation hose and the fuel vapor feed hose. TEXT IN ILLUSTRATION *1 Ventilation Hose *2 Fuel Vapor Feed Hose Loosen the hose clamp and separate the air cleaner hose from the throttle body. Remove the 2 bolts and remove the air cleaner assembly.
  14. REMOVE THROTTLE BODY Disconnect the 2 water by-pass hoses from the throttle body. Disconnect the throttle body connector and wire harness clamp. Remove the 4 bolts, throttle body and wire harness clamp stay. Remove the gasket from the intake air surge tank assembly.
  1. INSPECT ACCELERATOR PEDAL ASSEMBLY Connect the Techstream to the DLC3. Turn the engine switch on (IG). Turn the Techstream on. Enter the following menus: Powertrain / Engine / Data List / Accel Sensor Out No. 1 and Accel Sensor Out No. 2. Read the values displayed on the Techstream. Standard Voltage Tester Display Condition Specified Condition Accel Sensor Out No. 1 Accelerator pedal is released 0.5 to 1.1 V Accelerator pedal is fully depressed 2.6 to 4.5 V Standard Voltage Tester Display Condition Specified Condition Accel Sensor Out No. 2 Accelerator pedal is released 1.2 to 2.0 V Accelerator pedal is fully depressed 3.4 to 4.8 V If the result is not as specified, check the accelerator pedal assembly, wire harness or ECM.

Scheme 16

Scheme 16: REMOVAL
Scheme 16: REMOVAL
  1. REMOVE NO. 1 INSTRUMENT PANEL UNDER COVER SUB-ASSEMBLY
  2. REMOVE ACCELERATOR PEDAL ASSEMBLY Disconnect the accelerator pedal assembly connector. Remove the 2 nuts and accelerator pedal assembly. NOTE: Avoid physical shocks to the accelerator pedal assembly. Do not disassemble the accelerator pedal assembly.

Note. Perform the MAF meter inspection according to the following procedure. Only replace the MAF meter when the MAF value in the Data List (with the engine stopped) is not within the normal operating range or there is foreign matter on the MAF meter platinum hot wire (heater).

  1. INSPECT MASS AIR FLOW METER Read the values using the Techstream (MAF). NOTE: Perform the inspection with the vehicle indoors and on a level surface. Perform the inspection of the MAF meter while it is installed to the air cleaner case (installed to the vehicle). During the test, do not use an exhaust air duct on the exhaust pipe. Connect the Techstream to the DLC3. Turn the engine switch on (IG) (do not run the engine). Enter the following menus: Powertrain / Engine / Data List / MAF. Wait 30 seconds, and read the values on the Techstream. Standard Condition Tester Display Condition Specified Condition MAF Engine not running 30 seconds after engine switch turned on (IG) 0.53 g/sec. or less If the result is not as specified, replace the MAF meter. If the result is within the specified range, remove and inspect the MAF meter See step 1 .

Scheme 17

Scheme 17: REMOVAL
Scheme 17: REMOVAL
  1. REMOVE WINDSHIELD WIPER MOTOR AND LINK ASSEMBLY Remove the windshield wiper motor and link assembly. Refer to «REMOVAL»(ref-400809-S41356394852011051800000) .
  2. REMOVE FRONT SHOCK ABSORBER CAP (w/ Air Suspension) . Refer to «REMOVAL - Step 3»(ref-400810-S01269755922011051800000)
  3. REMOVE OUTER COWL TOP PANEL SUB-ASSEMBLY . Refer to «REMOVAL - Step 11»(ref-400778-S07130150422011051800000)
  4. REMOVE MASS AIR FLOW METER Separate the mass air flow meter connector. Remove the 2 screws and mass air flow meter.

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