Engine Control System: Diagnosis — Toyota Highlander I facelift (2003-2007)

ON-VEHICLE INSPECTION

CHECK THROTTLE BODY Listen to the throttle control motor operating sounds. Turn the ignition switch ON. When pressing the accelerator pedal position sensor lever, listen to the running motor. Make sure no friction noise comes from the motor. If friction noise exists, replace the throttle body. Check the throttle position sensor. Connect the hand-held tester or OBD II scan tool to the DLC3. Turn the ignition switch ON. Check that the check engine warning light does not light up. Under CURRENT DATA, the throttle valve opening percentage (THROTTLE POS) should be within the standard value range below. Standard throttle valve opening percentage: 60% or more If the percentage is less than 60%, replace the throttle position sensor. NOTE: When checking the standard throttle valve opening percentage, the transmission should be in the neutral position.
CHECK ACCELERATOR PEDAL POSITION SENSOR Turn the ignition switch ON. Under CURRENT DATA, the voltage of the throttle position sensor should be within the standard value range below. Standard: 0.6 to 1.0 V If the result is not as specified, replace the accelerator pedal position sensor.
CHECK CAMSHAFT TIMING OIL CONTROL VALVE (OCV) ASSY Connect the hand-held tester or OBD II scan tool to the DLC3. Turn the ignition switch ON. Start the engine and warm it up. Select the WT from the ACTIVE TEST menu. Check the engine speed when the OCV is operated by the hand-held tester or OBD II scan tool. Standard: ACTIVE TEST MENU Condition Specified Condition WT system is OFF (OCV is OFF) Normal engine speed WT system is ON (OCV is ON) Rough idle or engine stalled If the result is not as specified, replace the OCV assy.

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Scheme 1: INSPECTION

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INSPECT MASS AIR FLOW METER Check the output voltage. Apply battery voltage across terminals 1 (+B) and 2 (E2G). Connect the positive (+) tester probe to terminal 3 (VG), and negative (-) tester probe to terminal 2 (E2G). Blow air into the Mass Air Flow (MAF) meter, and check that the voltage fluctuates. Measure the resistance between terminals 4 (THA) and 5 (E2). Standard: RESISTANCE CHECK Condition Specified Condition -20°C (-4°F) 13.6 to 18.4 kohms 20°C(68°F) 2.21 to 2.69 kohms 60°C(140°F) 0.493 to 0.667 kohms If the result is not as specified, replace the MAF meter.
INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSY Measure the resistance between the terminals. Standard: 6.9 to 7.9 ohms at 20°C (68°F) If the result is not as specified, replace the OCV assy. Connect the battery's positive (+) lead to terminal 1 and negative (-) lead to terminal 2, and check the movement of the valve. NOTE: Confirm that the valve moves freely and does not become stuck In any position. If necessary, replace the OCV assy. HINT: If the valve cannot return properly because of foreign matter, a small pressure leak in the advanced direction may occur and a DTC will be output.
INSPECT ACCELERATOR PEDAL ROD ASSY Check the accelerator pedal position sensor (see «DTC P0120, P0122, P0123, P0220, P0223, P2135; THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A"/"B" VOLTAGE CORRELATION»(/toyota/highlander/i-facelift-2003-2007/remont/testing-diagnostics/#engine-control-system-sfi-2az-fe-diagnostics) ).
INSPECT THROTTLE BODY ASSY Check the throttle position sensor (see «DTC P0120, P0122, P0123, P0220, P0223, P2135; THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A"/"B" VOLTAGE CORRELATION»(/toyota/highlander/i-facelift-2003-2007/remont/testing-diagnostics/#engine-control-system-sfi-2az-fe-diagnostics) ). Check the throttle control motor. Measure the resistance between terminals 2 (M+) and 1 (M-). Resistance: 0.3 to 100 ohms at 20°C (68°F) If the result is not as specified, replace the throttle body assy.
INSPECT ENGINE COOLANT TEMPERATURE SENSOR Measure the resistance between terminals 1 and 2. Standard: RESISTANCE CHECK Condition Specified Condition 20°C (68°F) 2.32 to 2.59 kohms 80°C (176°F) 0.310 to 0.326 kohms If the result is not as specified, replace the sensor. NOTE: If checking the ECT sensor In the water, keep the terminals dry. After the check, wipe the sensor dry.
INSPECT KNOCK SENSOR Measure the resistance between the terminals. Standard: 120 to 280 kohms at 20°C (68°F) If the result is not as specified, replace the sensor.
INSPECT RELAY (Marking: EFI, A/F) Remove the EFI relay from the engine room J/B, Remove the A/F relay from the engine room R/B No. 2. Measure the resistance of the relay. Standard: RESISTANCE CHECK Tester Connection Specified Condition 3-5 10kohms or higher 3-5 Below 1ohms(when battery voltage is applied to terminals 1 and 2) If the result is not as specified, replace the relay.
INSPECT CIRCUIT OPENING RELAY Remove the circuit opening relay from the R/B sub-assy Measure the resistance of the relay. Standard: RESISTANCE CHECK Tester Connection Specified Condition 3-5 10kohms or higher 3-5 Below 1ohms(when battery voltage is applied to terminals 1 and 2) If the result is not as specified, replace the relay.

Scheme 8

Scheme 8: COMPONENTS

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Scheme 9: REPLACEMENT

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Scheme 11

DRAIN ENGINE COOLANT (See «COOLANT (2AZ-FE)»(ref-226412-S07429961942006032800000) )
REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE THROTTLE BODY ASSY Disconnect the throttle control motor & throttle position sensor connector. Disconnect the vacuum hose from the throttle body. Disconnect the 2 water by-pass hoses. Remove the 4 bolts, fuel pipe support and throttle body. Remove the gasket.
INSTALL THROTTLE BODY ASSY Install a new gasket to the intake manifold, as shown in the illustration. Install the throttle body and fuel pipe support with the 4 bolts. Torque: 30 Nm (305 kgf.cm, 22 ft.lbf) Connect the 2 water by-pass hoses to the throttle body. Connect the throttle control motor & throttle position sensor connector. Connect the vacuum hose to the throttle body.
INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
ADD ENGINE COOLANT (See «COOLANT (2AZ-FE)»(ref-226412-S07429961942006032800000) )
CHECK FOR ENGINE COOLANT LEAKS (See «COOLING SYSTEM (2AZ-FE)»(ref-226412-S29116418352006032800000) )

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Scheme 12: REPLACEMENT

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DRAIN ENGINE COOLANT (See «COOLANT (2AZ-FE)»(ref-226412-S07429961942006032800000) )
REMOVE AIR CLEANER CAP WITH AIR CLEANER HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE THROTTLE BODY ASSY (See «REPLACEMENT»(ref-226406-S41150982822006032800000) )
REMOVE INTAKE MANIFOLD Remove the 5 bolts, 2 nuts, intake manifold and gasket.
REMOVE KNOCK SENSOR Disconnect the sensor connector. Remove the nut and sensor.
INSTALL KNOCK SENSOR Install the sensor with the nut Torque: 20 N.m (199 kgf.cm, 14 ft.lbf) HINT: Angling the knock sensor below the horizontal (below 0°) is recommended. Connect the sensor connector.
INSTALL INTAKE MANIFOLD Install a new gasket and the intake manifold with the 5 bolts and 2 nuts Torque: 30 N m (305 kgf cm, 22 ft lbf)
INSTALL THROTTLE BODY ASSY (See «REPLACEMENT»(ref-226406-S41150982822006032800000) )
INSTALL AIR CLEANER CAP WITH AIR CLEANER HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
ADD ENGINE COOLANT (See «COOLANT (2AZ-FE)»(ref-226412-S07429961942006032800000) )
CHECK FOR ENGINE COOLANT LEAKS (See «COOLING SYSTEM (2AZ-FE)»(ref-226412-S29116418352006032800000) )

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Scheme 16: REPLACEMENT

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DISCONNECT BATTERY NEGATIVE TERMINAL
REMOVE FRONT DOOR SCUFF PLATE RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE COWL SIDE TRIM SUB-ASSY RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE GLOVE COMPARTMENT DOOR ASSY (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE INSTRUMENT PANEL FINISH PANEL LOWER NO.2 (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE ECM Remove the 2 wire harness clamps. Disconnect the 5 ECM connectors. Remove the 2 nuts and ECM.
REMOVE ECM BRACKET NO.1 Remove the 2 screws and ECM bracket.
REMOVE ECM BRACKET NO.2 Remove the 2 screws and ECM bracket.
INSTALL ECM BRACKET NO. 2 Install the ECM bracket with the 2 screws.
INSTALL ECM BRACKET NO. 1 Install the ECM bracket with the 2 screws.
INSTALL ECM Install the 2 wire harness clamps Connect the 5 ECM connectors. Install the ECM with the 2 nuts. Torque: 5.5 N m (56 kgf.cm, 49 in. lbf)
INSTALL INSTRUMENT PANEL FINISH PANEL LOWER NO.2 (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL GLOVE COMPARTMENT DOOR ASSY (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL COWL SIDE TRIM SUB-ASSY RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL FRONT DOOR SCUFF PLATE RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
CONNECT BATTERY NEGATIVE TERMINAL

Scheme 21

Scheme 21: REPLACEMENT

REMOVE ACCELERATOR PEDAL ROD ASSY Disconnect the accelerator pedal position sensor connector. Remove the 2 bolts and pedal rod.
INSTALL ACCELERATOR PEDAL ROD ASSY Install the pedal rod with the 2 bolts. Torque: 4.9 N m (50 kgf cm, 43 in.lbf) Connect the accelerator pedal position sensor connector.

CHECK THROTTLE BODY Listen to the throttle control motor operating sounds. Turn the ignition switch ON. When pressing the accelerator pedal position sensor lever, listen to the running motor. Make sure no friction noise comes from the motor. If friction noise exists, replace the throttle body. Inspect the throttle position sensor. Connect the hand-held tester or OBD II scan tool to the DLC3. Turn the ignition switch ON. Check that the MIL is off. Under CURRENT DATA, the throttle valve opening percentage (THROTTLE POS) should be within the standard value range below. Standard throttle valve opening percentage: 60 % or more If the percentage is less than 60 %, replace the throttle position sensor. NOTE: When checking the standard throttle valve opening percentage, the transmission should be in the neutral position.
CHECK ACCELERATOR PEDAL POSITION SENSOR Turn the ignition switch ON. Under CURRENT DATA, the voltage of the throttle position sensor should be within the standard value range below. Standard: 0.6 to 1.0 V If the result is not as specified, replace the accelerator pedal position sensor.
CHECK CAMSHAFT TIMING OIL CONTROL VALVE (OCV) ASSY Connect the hand-held tester or OBD II scan tool to the DLC3. Turn the ignition switch ON. Start the engine and warm it up. Select the WT from the ACTIVE TEST menu. Check the engine speed when the OCV is operated by the hand-held tester or OBD II scan tool. Standard: RESISTANCE CHECK Condition Specified Condition WT system is OFF (OCV is OFF) Normal engine speed WT system is ON (OCV is ON) Rough idle or engine stalled If the result is not as specified, replace the OCV assy.

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Scheme 22: INSPECTION

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INSPECT MASS AIR FLOW METER Check the output voltage. Apply battery voltage across terminals 1 (+B) and 2 (E2G). Connect the positive (+) tester probe to terminal 3 (VG), and negative (-) tester probe to terminal 2 (E2G). Blow air into the Mass Air Flow (MAF) meter, and check that the voltage fluctuates. Measure the resistance between terminals 4 (THA) and 5 (E2). Standard: RESISTANCE CHECK Condition Specified Condition -20°C(-4°F) 13.6 to 18.4 kohms 20°C(68°F) 2.21 to 2.69 kohms 60°C(140°F) 0.493 to 0.667 kohms If the result is not as specified, replace the MAF meter.
INSPECT CAMSHAFT TIMING OIL CONTROL VALVE ASSY Measure the resistance between the terminals. Standard: 6.9 to 7.9 ohms at 20°C (68°F) If the result is not as specified, replace the OCV assy. Connect the battery's positive (+) lead to terminal 1 and negative (-) lead to terminal 2, and check the movement of the valve. NOTE: Confirm that the valve moves freely and does not become stuck In any position. If necessary, replace the OCV assy. HINT: If the valve cannot return properly because of foreign matter, a small pressure leak in the advanced direction may occur and a DTC will be output.
INSPECT ACCELERATOR PEDAL ROD ASSY Check the accelerator pedal position sensor (see «DTC P0120, P0122, P0123, P0220, P0223, P2135; THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A"/"B" VOLTAGE CORRELATION»(/toyota/highlander/i-facelift-2003-2007/remont/testing-diagnostics/#engine-control-system-sfi-2az-fe-diagnostics) ).
INSPECT THROTTLE BODY ASSY Check the throttle position sensor (see «DTC P0120, P0122, P0123, P0220, P0223, P2135; THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT HIGH INPUT, THROTTLE/PEDAL POSITION SENSOR/SWITCH "A"/"B" VOLTAGE CORRELATION»(/toyota/highlander/i-facelift-2003-2007/remont/testing-diagnostics/#engine-control-system-sfi-2az-fe-diagnostics) ). Check the throttle control motor. Measure the resistance between terminals 2 (M+) and 1 (M-). Resistance: 0.3 to 100 ohms at 20°C (68°F) If the result is not as specified, replace the throttle body assy.
INSPECT ENGINE COOLANT TEMPERATURE SENSOR Measure the resistance between terminals Standard: RESISTANCE CHECK Condition Specified Condition 20°C(68°F) 2.32 to 2.59 kohms 80°C(176°F) 0.310 to 0.326 kohms If the result is not as specified, replace the sensor. NOTE: If checking the ECT sensor In the water, keep the terminals dry. After the check, wipe the sensor dry.
INSPECT KNOCK SENSOR Measure the resistance between the terminals. Resistance: 120 to 280 kohms at 20°C (68°F) If the result is not as specified, replace the sensor.
INSPECT RELAY (Marking: EFI, A/F) Remove the EFI relay from the engine room J/B, Remove the A/F relay from the engine room R/B No. 2. Measure the resistance of the relay. Standard: RESISTANCE CHECK Tester Connection Specified Condition 3-5 10 kohms or higher 3-5 Below 1ohms (when battery voltage is applied to terminals 1 and 2) If the result is not as specified, replace the relay.
INSPECT CIRCUIT OPENING RELAY Remove the circuit opening relay from the R/B sub-assy. Measure the resistance of the relay. Standard: RESISTANCE CHECK Tester Connection Specified Condition 3-5 10 kohms or higher 3-5 Below 1ohms (when battery voltage is applied to terminals 1 and 2) If the result is not as specified, replace the relay.

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Scheme 29: COMPONENTS

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Scheme 31

Scheme 31: REPLACEMENT

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DRAIN ENGINE COOLANT (See «COOLANT (3MZ-FE)»(ref-226412-S16627119532006032800000) )
REMOVE FRONT SUSPENSION BRACE SUB-ASSY UPPER CENTER Remove the 2 nuts and upper brace.
REMOVE V-BANK COVER SUB-ASSY Using a socket hexagon wrench 5, remove the 3 nuts. Remove the V-bank cover.
REMOVE AIR CLEANER INLET ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE AIR CLEANER ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE INTAKE AIR RESONATOR Remove the ventilation hose No. 2. Remove the fuel vapor feed hose from the 2 hose clamps. Loosen the air cleaner hose clamp bolt, and then remove the intake air resonator.
REMOVE THROTTLE BODY ASSY Disconnect the throttle control motor & throttle position sensor connector. Disconnect the water by-pass hose No. 2. Disconnect the water by-pass hose No. 3. Remove the 2 bolts, 2 nuts and throttle body. Remove the gasket.
INSTALL THROTTLE BODY ASSY Install a new gasket to the intake air connector. Install the throttle body with the 2 bolts and 2 nuts. Torque: 11 N m (112 kgf.cm, 8 ft.lbf) Connect the water by-pass hose No. 3. Connect the water by-pass hose No. 2. Connect the throttle control motor & throttle position sensor connector.
INSTALL INTAKE AIR RESONATOR
INSTALL AIR CLEANER ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
INSTALL AIR CLEANER INLET ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
CHECK CONNECTION OF VACUUM HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
ADD ENGINE COOLANT (See «COOLANT (3MZ-FE)»(ref-226412-S16627119532006032800000) )
CHECK FOR ENGINE COOLANT LEAKS (See «COOLING SYSTEM (2AZ-FE)»(ref-226412-S29116418352006032800000) )
INSTALL V-BANK COVER SUB-ASSY Fit the 2 retainers and install the V-bank cover. Using a socket hexagon wrench 5, tighten the 3 nuts. Torque: 7.9 N.m (81 kgf.cm, 70 in.lbf)
INSTALL FRONT SUSPENSION BRACE SUB-ASSY UPPER CENTER Install the upper brace with the 2 nuts. Torque: 80 N.m (815 kgf.cm, 59 ft.lbf)

Scheme 35

Scheme 35: REPLACEMENT

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DISCHARGE FUEL SYSTEM PRESSURE (See «FUEL SYSTEM (3MZ-FE)»(/toyota/highlander/i-facelift-2003-2007/remont/fuel-system/#engine-fuel-system) )
DRAIN ENGINE COOLANT (See «COOLANT (3MZ-FE)»(ref-226412-S16627119532006032800000) )
REMOVE V-BANK COVER SUB-ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE AIR CLEANER CAP SUB-ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE EMISSION CONTROL VALVE SET (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE INTAKE AIR SURGE TANK (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE INTAKE MANIFOLD Disconnect the fuel pipe No. 1. Remove the fuel pipe clamp. Pinch the tube connector and pull out the fuel pipe No. 1. NOTE: Check the connector for dirt, mud or other contamination. Clean if necessary. Be sure to keep the tube connector, pipe and O-ring clean. They can become contaminated easily. Do not use tools when disconnecting the fuel pipe. Do not bend or twist the nylon tube. Protect the connector by covering it with a vinyl or plastic bag. When the pipe and the connector are stuck, push and pull the connector to release it. Then pull the connector out carefully. Lock the hose clamp, as shown in the illustration. Disconnect the heater inlet water hose. Remove the nut and disconnect the ground cable. Disconnect the 6 fuel injector connectors. Loosen and remove the intake manifold's 9 bolts and 2 nuts little by little in the numerical order shown in the illustration. Remove the intake manifold. NOTE: Fully removing each bolt and nut one by one may damage the intake manifold, bolts and nuts.
REMOVE ENGINE MOVING CONTROL ROD (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
REMOVE WATER OUTLET Disconnect the radiator hose inlet. Disconnect the ECT sensor connector. Remove the clamp. Remove the 2 bolts, 2 nuts and 2 washers. Lock the hose clamp as shown in the illustration. Then remove the water outlet together with the water by-pass hose No. 1. Remove the 2 gaskets from the 2 cylinder heads.
REMOVE KNOCK SENSOR Disconnect the 2 sensor connectors. Remove the 2 nuts and 2 sensors.
INSTALL KNOCK SENSOR Install the 2 sensors with the 2 nuts, as shown in the illustration. Torque: 20 N.m (199 kgf.cm, 14 ft.lbf) Connect the 2 sensor connectors.
INSTALL WATER OUTLET Install 2 new gaskets to the 2 cylinder heads. Install the water outlet together with the water by-pass hose No. 1 and unlock the hose clamp. Tighten the 2 bolts, 2 nuts and 2 washers. Torque: 15 N.m (153 kgf.cm, 11 ft.lbf) Install the clamp. Connect the ECT sensor connector. Connect the radiator hose inlet.
INSTALL ENGINE MOVING CONTROL ROD (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
INSTALL INTAKE MANIFOLD Tighten the intake manifolds's 9 bolts and 2 nuts little by little in the numerical order shown in the illustration. Torque: 15 N.m (153 kgf.cm, 11 ft.lbf) NOTE: In this case, fully tightening one of these bolts or nuts without partially tightening the other bolts or nuts in the group may damage the intake manifold, bolts and nuts. Retighten the water outlet mounting bolts and nuts. Torque: 15 N.m (153 kgf.cm, 11 ft.lbf) Install the ground cable with the nut. Torque: 8.4 N.m (86 kgf.cm, 74 in.lbf) Connect the heater inlet water hose. Connect the fuel pipe No. 1. Push the quick connector into the pipe until it makes "click" sound. NOTE: Check if there is any damage or contamination on the connected part. After connecting, confirm that the connector and pipe are securely connected by trying to pull them apart. Install the fuel pipe clamp.
INSTALL INTAKE AIR SURGE TANK (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
INSTALL EMISSION CONTROL VALVE SET (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
INSTALL AIR CLEANER CAP SUB-ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
CHECK CONNECTION OF VACUUM HOSE (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )
ADD ENGINE COOLANT (See «COOLANT (3MZ-FE)»(ref-226412-S16627119532006032800000) )
CHECK FOR ENGINE COOLANT LEAKS (See «COOLING SYSTEM (2AZ-FE)»(ref-226412-S29116418352006032800000) )
CHECK FOR FUEL LEAKS
INSTALL V-BANK COVER SUB-ASSY (See «REPLACEMENT»(/toyota/highlander/i-facelift-2003-2007/remont/accessory-drive-belts/#engine-mechanical) )

Scheme 46

Scheme 46: REPLACEMENT

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Scheme 50

DISCONNECT BATTERY NEGATIVE TERMINAL
REMOVE FRONT DOOR SCUFF PLATE RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE COWL SIDE TRIM SUB-ASSY RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE GLOVE COMPARTMENT DOOR ASSY (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE INSTRUMENT PANEL FINISH PANEL LOWER NO.2 (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
REMOVE ECM Remove the 2 wire harness clamps. Disconnect the 5 ECM connectors. Remove the 2 nuts and ECM.
REMOVE ECM BRACKET NO. 1 Remove the 2 screws and ECM bracket.
REMOVE ECM BRACKET NO. 2 Remove the 2 screws and ECM bracket.
INSTALL ECM BRACKET NO. 2 Install the ECM bracket with the 2 screws.
INSTALL ECM BRACKET NO. 1 Install the ECM bracket with the 2 screws.
INSTALL ECM Install the 2 wire harness clamps. Connect the 5 ECM connectors. Install the ECM with the 2 nuts. Torque: 5.5 N.m (56 kgf.cm, 49 In.lbf)
INSTALL INSTRUMENT PANEL FINISH PANEL LOWER NO.2 (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL GLOVE COMPARTMENT DOOR ASSY (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL COWL SIDE TRIM SUB-ASSY RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
INSTALL FRONT DOOR SCUFF PLATE RH (See «REPLACEMENT»(ref-226443-S32618601872006032900000) )
CONNECT BATTERY NEGATIVE TERMINAL

Engine Control System: Diagnosis Toyota Highlander I facelift