Engine Control System (Service Information): Diagnosis Lexus GS IV

ON-VEHICLE INSPECTION [03/2012 - ]

1. INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Connect the Techstream to the DLC3. Put the engine in inspection mode. Refer to «INSPECTION MODE PROCEDURE [03/2012 - ]»(ref-600412-S34816019962014022400000) . Start the engine. Turn the Techstream on. Inspect the oil control valve (for intake camshaft). Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 1). Check the engine speed when the oil control valve is operated using the Techstream. HINT: The test is not possible with the shift lever in P during charge control. Move the shift lever to N to perform the test. Standard Condition Control Range Specified Condition OFF Normal engine speed ON Rough idle or engine stalls (soon after oil control valve switched from OFF to ON) If the operation is not as specified, check the oil control valve, wire harness and ECM. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT System (Bank 2). Check the engine speed when the oil control valve is operated using the Techstream. HINT: The test is not possible with the shift lever in P during charge control. Move the shift lever to N to perform the test. Standard Condition Control Range Specified Condition OFF Normal engine speed ON Rough idle or engine stalls (soon after oil control valve switched from OFF to ON) If the operation 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 and ECT / Active Test / Control the VVT Exhaust Linear (Bank 1). Check the engine speed when the oil control valve is operated using the Techstream. HINT: The test is not possible with the shift lever in P during charge control. Move the shift lever to N to perform the test. Standard Condition Control Range Specified Condition -100% Normal engine speed 100% Rough idle or engine stalls (soon after oil control valve switched to 100%) If the operation is not as specified, check the oil control valve, wire harness and ECM. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the VVT Exhaust Linear (Bank 2). Check the engine speed when the oil control valve is operated using the Techstream. HINT: The test is not possible with the shift lever in P during charge control. Move the shift lever to N to perform the test. Standard Condition Control Range Specified Condition -100% Normal engine speed 100% Rough idle or engine stalls (soon after oil control valve switched to 100%) If the operation is not as specified, check the oil control valve, wire harness and ECM.

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1. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 3»(ref-600560-S04080038042014022400000)
2. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 1) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
3. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 1) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
4. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 2) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.
5. REMOVE CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 2) Disconnect the oil control valve connector. Remove the bolt and oil control valve. Remove the O-ring from the oil control valve.

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1. INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSEMBLY Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 - 2 20°C (68°F) 6.9 to 7.9 ohms If the result is not as specified, replace the oil control valve. Connect a battery's positive (+) lead to terminal 1 and negative (-) lead to terminal 2, and check the movement of the valve. OK Condition Specified Condition Battery positive (+) voltage is applied Valve moves in left arrow direction shown in illustration Battery positive (+) voltage is cut off Valve moves in right arrow direction shown in illustration TEXT IN ILLUSTRATION *a Component without harness connected (Camshaft Timing Oil Control Valve) If the result is not as specified, replace the oil control valve. NOTE: Accumulation of foreign matter can cause minor pressure leaks. Minor pressure leaks in the intake side oil control valve will cause the intake camshaft to advance. Minor pressure leaks in the exhaust side oil control valve will cause the exhaust camshaft to retard. The inappropriate camshaft timing that results from these leaks will cause a DTC to be set.

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1. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 2) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. TEXT IN ILLUSTRATION *1 O-Ring Install the oil control valve with the bolt. Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf) NOTE: Do not allow foreign matter to contact the oil seal face of the camshaft timing oil control valve (the surface that contacts the cylinder head cover). Be careful that the O-ring is not cracked when installing the camshaft timing oil control valve. Connect the camshaft timing oil control valve connector.
2. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 2) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. TEXT IN ILLUSTRATION *1 O-Ring Install the oil control valve with the bolt. Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf) NOTE: Do not allow foreign matter to contact the oil seal face of the camshaft timing oil control valve (the surface that contacts the cylinder head cover). Be careful that the O-ring is not cracked when installing the camshaft timing oil control valve. Connect the camshaft timing oil control valve connector.
3. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Intake Side of Bank 1) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. TEXT IN ILLUSTRATION *1 O-Ring Install the oil control valve with the bolt. Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf) NOTE: Do not allow foreign matter to contact the oil seal face of the camshaft timing oil control valve (the surface that contacts the cylinder head cover). Be careful that the O-ring is not cracked when installing the camshaft timing oil control valve. Connect the camshaft timing oil control valve connector.
4. INSTALL CAMSHAFT TIMING OIL CONTROL VALVE (for Exhaust Side of Bank 1) Apply a light coat of engine oil to a new O-ring and install it to the oil control valve. TEXT IN ILLUSTRATION *1 O-Ring Install the oil control valve with the bolt. Torque: 10 N*m (102 kgf*cm, 7 ft.*lbf) NOTE: Do not allow foreign matter to contact the oil seal face of the camshaft timing oil control valve (the surface that contacts the cylinder head cover). Be careful that the O-ring is not cracked when installing the camshaft timing oil control valve. Connect the camshaft timing oil control valve connector.
5. INSTALL V-BANK COVER SUB-ASSEMBLY . Refer to «INSTALLATION [03/2012 - ] - Step 116»(ref-600560-S18093750712014022400000)

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1. INSPECT THROTTLE BODY ASSEMBLY Put the vehicle in inspection mode. Refer to «INSPECTION MODE PROCEDURE [03/2012 - ]»(ref-600412-S34816019962014022400000) . Start the engine and check that the MIL is not illuminated. After the engine is warmed up, check that the idle speed is within the specified range when the A/C is switched off. Standard Condition Engine Idle Speed A/C switched off 950 to 1050 rpm NOTE: Be sure to perform this step with all accessories off. Make sure that park (P) is selected.

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1. REMOVE ENGINE ROOM SIDE COVER . Refer to «REMOVAL [03/2012 - ] - Step 1»(ref-600560-S04080038042014022400000)
2. REMOVE COOL AIR INTAKE DUCT SEAL . Refer to «REMOVAL [03/2012 - ] - Step 2»(ref-600560-S04080038042014022400000)
3. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 3»(ref-600560-S04080038042014022400000)
4. REMOVE ENGINE UNDER COVER . Refer to «REMOVAL [03/2012 - ] - Step 21»(ref-600560-S04080038042014022400000)
5. DRAIN ENGINE COOLANT . Refer to «REPLACEMENT [03/2012 - ] - Step 4»(ref-600564-S07414681062014022400000)
6. DISCONNECT NO. 2 VENTILATION HOSE Disconnect the No. 2 ventilation hose from the cylinder head cover.
7. REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE Disconnect the mass air flow meter connector. Disconnect the clamp from the air cleaner. Disconnect the VSV hose. Disconnect the 4 clamps. Remove the hose clamp and air cleaner cap with air cleaner hose.
8. REMOVE THROTTLE BODY WITH MOTOR ASSEMBLY Disconnect the throttle motor connector. Remove the 4 bolts and disconnect the throttle body with motor assembly from the intake air surge tank. Disconnect the 2 water by-pass hoses from the throttle body with motor assembly. Remove the throttle body with motor assembly and gasket.

INSPECTION [03/2012 - ]

1. INSPECT THROTTLE BODY WITH MOTOR ASSEMBLY Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 (M-) - 2 (M+) 20°C (68°F) 0.3 to 100 ohms TEXT IN ILLUSTRATION *a Component without harness connected (Throttle Body with Motor) If the result is not as specified, replace the throttle body.

Note. Perform the mass air flow meter inspection according to the procedure below. Only replace the mass air flow meter when the mass air flow value in the Data List (with the engine stopped) is not within the normal operating range.

1. CHECK MASS AIR FLOW METER SUB-ASSEMBLY Read the value using the Techstream. NOTE: Turn off the engine. Perform the inspection with the vehicle indoors and on a level surface. Perform the inspection of the mass air flow meter while it is installed to the air cleaner case (installed to the vehicle). During the test, do not use the exhaust air duct to perform suction on the exhaust pipe. Turn the power switch on (IG) (do not run the engine). Turn the Techstream on. Enter the following menus: Powertrain / Engine and ECT / Data List / MAF. Wait 30 seconds, and read the values on the Techstream. Standard Condition Item Condition Specified Condition MAF Engine not running 30 seconds after turning power switch on 0.57 g/sec or less If the result is not as specified, replace the mass air flow meter sub-assembly. If the result is as specified, inspect the mass air flow meter sub-assembly. Refer to «INSPECTION [03/2012 - ]»(ref-600565-S11343572192014022400000) .

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1. REMOVE MASS AIR FLOW METER Disconnect the clamp and mass air flow meter connector. Remove the 2 screws and mass air flow meter.

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1. INSPECT MASS AIR FLOW METER SUB-ASSEMBLY Perform a visual check for any foreign matter on the platinum hot wire (heater) of the mass air flow meter shown in the illustration. OK There is no foreign matter. TEXT IN ILLUSTRATION *1 Platinum Hot Wire (Heater) If the result is not as specified, replace the mass air flow meter. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 (THA) - 2 (E2) -20°C (-4°F) 13.6 to 18.4 kohms 1 (THA) - 2 (E2) 20°C (68°F) 2.21 to 2.69 kohms 1 (THA) - 2 (E2) 60°C (140°F) 0.49 to 0.67 kohms TEXT IN ILLUSTRATION *a Component without harness connected (Mass Air Flow Meter Sub-assembly) If the result is not as specified, replace the mass air flow meter sub-assembly.

1. INSPECT CRANKSHAFT POSITION SENSOR Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 - 2 Cold 1630 to 2740 ohms Hot 2065 to 3225 ohms NOTE: In the table above, the terms "Cold" and "Hot" refer to the temperature of the coils. "Cold" means approximately -10 to 50°C (14 to 122°F). "Hot" means approximately 50 to 100°C (122 to 212°F). If the resistance is not as specified, replace the crankshaft position sensor.

1. INSPECT KNOCK SENSOR Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 - 2 20°C (68°F) 120 to 280 kohms If the result is not as specified, replace the knock sensor.

1. INSPECT MANIFOLD ABSOLUTE PRESSURE SENSOR Check the power source voltage. Disconnect the manifold absolute pressure sensor connector. Turn the power switch on (IG). Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Condition Specified Condition F12-3 (VC) - F12-2 (E2) Power switch on (IG) 4.75 to 5.25 V F12-1 (PIM) - F12-2 (E2) Power switch on (IG) 3.0 to 5.0 V TEXT IN ILLUSTRATION *a Front view of wire harness connector (to Manifold Absolute Pressure Sensor) Connect the manifold absolute pressure sensor connector. Check the intake manifold pressure. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Powertrain / Engine and ECT / Data List / Primary / MAP. Read the MAP value. OK Same value as the actual atmospheric pressure HINT: Standard atmospheric pressure is 101 kPa(abs) [760 mmHg(abs)]. For every 100 m (328 ft) increase in altitude, pressure drops by 1 kPa (7.5 mmHg). The pressure also varies due to the weather (high atmospheric pressure, low atmospheric pressure). Also, check "Atmosphere Pressure" in the Data List.

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1. REMOVE V-BANK COVER SUB-ASSEMBLY . Refer to «REMOVAL [03/2012 - ] - Step 3»(ref-600560-S04080038042014022400000)
2. REMOVE MANIFOLD ABSOLUTE PRESSURE SENSOR Disconnect the connector. Remove the 2 bolts and manifold absolute pressure sensor.

1. INSPECT AIR FUEL RATIO SENSOR Measure the resistance according to the value(s) in the table below. Standard Resistance (for Bank 1) Tester Connection Condition Specified Condition 1 (HA1A) - 2 (+B) 20°C (68°F) 1.6 to 3.2 ohms 1 (HA1A) - 4 (A1A-) Always 10 kohms or higher Standard Resistance (for Bank 2) Tester Connection Condition Specified Condition 1 (HA2A) - 2 (+B) 20°C (68°F) 1.6 to 3.2 ohms 1 (HA2A) - 4 (A2A-) Always 10 kohms or higher TEXT IN ILLUSTRATION *A for Bank 1 *B for Bank 2 *a Component without harness connected (Air Fuel Ratio Sensor) If the result is not as specified, replace the air fuel ratio sensor.

1. INSPECT HEATED OXYGEN SENSOR Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1 (HT1B) - 2 (+B) 20°C (68°F) 11 to 16 ohms 1 (HT1B) - 4 (E2) Always 10 kohms or higher 1 (HT2B) - 2 (+B) 20°C (68°F) 11 to 16 ohms 1 (HT2B) - 4 (E2) Always 10 kohms or higher TEXT IN ILLUSTRATION *a Component without harness connected (Heated Oxygen Sensor for Bank 1) *b Component without harness connected (Heated Oxygen Sensor for Bank 2) If the result is not as specified, replace the heated oxygen sensor.

1. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN1) Check the EFI MAIN fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition EFI MAIN fuse Always Below 1 ohms If the result is not as specified, replace the EFI MAIN fuse. Check the EFI No. 2 fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition EFI No. 2 fuse Always Below 1 ohms If the result is not as specified, replace the EFI No. 2 fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1D-1 - 1E-16 Battery voltage not applied to terminals 1E-6 and 1E-10 10 kohms or higher Battery voltage applied to terminals 1E-6 and 1E-10 Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Integration Relay) If the result is not as specified, replace the No. 1 integration relay.
2. INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN2) Check the F/PMP fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition F/PMP fuse Always Below 1 ohms If the result is not as specified, replace the F/PMP fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1D-1 - 1F-12 Battery voltage not applied to terminals 1F-10 and 1E-10 10 kohms or higher Battery voltage applied to terminals 1F-10 and 1E-10 Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Integration Relay) If the result is not as specified, replace the No. 1 integration relay.
3. INSPECT NO. 1 INTEGRATION RELAY (INJ) Check the EDU fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition EDU fuse Always Below 1 ohms If the result is not as specified, replace the EDU fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1D-1 - 1F-11 Battery voltage not applied to terminals 1F-10 and 1E-19 10 kohms or higher Battery voltage applied to terminals 1F-10 and 1E-19 Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Integration Relay) If the result is not as specified, replace the No. 1 integration relay.
4. INSPECT NO. 1 INTEGRATION RELAY (IG2) Check the IG2 MAIN fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition IG2 MAIN fuse Always Below 1 ohms If the result is not as specified, replace the IG2 MAIN fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1D-1 - 1F-2 Battery voltage not applied to terminals 1E-2 and 1E-10 10 kohms or higher Battery voltage applied to terminals 1E-2 and 1E-10 Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Integration Relay) If the result is not as specified, replace the No. 1 integration relay.
5. INSPECT NO. 1 INTEGRATION RELAY (A/F) Check the A/F fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition A/F fuse Always Below 1 ohms If the result is not as specified, replace the A/F fuse. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition 1D-1 - 1F-4 Battery voltage not applied to terminals 1E-16 and 1E-10 10 kohms or higher Battery voltage applied to terminals 1E-16 and 1E-10 Below 1 ohms TEXT IN ILLUSTRATION *a Component without harness connected (No. 1 Integration Relay) If the result is not as specified, replace the No. 1 integration relay.