Steering System: Diagnosis — Toyota Corolla IX (2000-2004)

PROBLEM SYMPTOMS TABLE

Use the table below to help you find the cause of the problem. The numbers indicate the priority of the likely cause of the problem. Check each part in the order shown. If necessary, repair or replace these parts.

Scheme 1

Scheme 1: PROBLEM SYMPTOMS TABLE

Inspect Drive Belt

Note. Cracks on the rib side of a belt are considered acceptable. If the missing chunks from the ribs are found on the drive belt, it should be replaced. After installing a drive belt, check that it fits properly in the ribbed grooves. Check with your hand to confirm that the drive belt has not slipped out of the groove on the bottom of the pulley.

Visually check the drive belt for excessive wear, frayed cords, etc.

If any defect has been found, replace the drive belt.

Scheme 2

Scheme 2: BLEEDING

Check fluid level. See «INSPECTION»(ref-170954-S22740049442005012400000).
Jack up front of vehicle and support it with stands .
Turn steering wheel . With the engine stopped, turn the steering wheel slowly from lock to lock several times.
Lower vehicle .
start Engine . Run the engine at idle for a few minutes.
Turn steering wheel : With the engine idling, turn the steering wheel to left or right full lock position and keep it there for 2 - 3 seconds, then turn the steering wheel to the opposite full lock position and keep it there for 2 - 3 seconds. Repeat ( a ) several times.
Stop engine .
Check for foaming or emulsification . If the system has to be bled twice specifically because of foaming or emulsification, check for fluid leaks in the system.
Check fluid level. See «INSPECTION»(ref-170954-S22740049442005012400000).

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Scheme 3: INSPECTION

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Check fluid level: Keep the vehicle level. NOTE: HINT: Check that the fluid level is within the HOT level range on the reservoir. If the fluid is cold, check that it is within the COLD level range. With the engine stopped, check the fluid level in the oil reservoir. If necessary, add fluid. Fluid: ATF DEXRON(R)II or III. Start the engine and run it at idle. Turn the steering wheel from lock to lock several times to boost fluid temperature. Fluid temperature: 80°C (176°F). Check for foaming or emulsification. If there is foaming or emulsification, bleed power steering system. See «REPLACEMENT»(ref-170954-S17588757932005012400000). With the engine idling, measure the fluid level in the oil reservoir. Stop the engine. Wait a few minutes and remeasure the fluid level in the oil reservoir. Maximum fluid level rise: 5 mm (0.20 in.) If a problem is found, bleed power steering system. See «REPLACEMENT»(ref-170954-S17588757932005012400000). Check the fluid level.
Check steering fluid pressure: Disconnect the pressure feed tube from the PS gear. See «REMOVAL»(ref-170954-S11872611462005012400000). NOTE: Check that the valve of the SST is in the open position. Connect SST, as shown in the illustration below. SST 09640-10010 (09641-01010, 09641-01020, 09641-01030). Bleed the power steering system. See «REPLACEMENT»(ref-170954-S17588757932005012400000). Start the engine and run it at idle. Turn the steering wheel from lock to lock several times to boost fluid temperature. Fluid temperature: 80°C (176°F). NOTE: Do not keep the valve closed for more than 10 seconds. Do not let the fluid temperature become too high. With the engine idling, close the valve of the SST and observe the reading on the SST. Minimum fluid pressure: 6,374 kPa (65 kgf/cm 2, 925 psi). With the engine idling, open the valve fully. NOTE: Do not turn the steering wheel. Measure the fluid pressure at engine speeds of 1,000 rpm and 3,000 rpm. Difference fluid pressure: 490 kPa (5 kgf/cm 2, 71 psi) or less. NOTE: Do not maintain lock position for more than 10 seconds. Do not let the fluid temperature become too high. With the engine idling and valve fully opened, turn the steering wheel to full lock. Minimum fluid pressure: 6,374 kPa (65 kgf/cm 2, 925 psi). Disconnect the SST. SST 09640-10010 (09641-01010, 09641-01020, 09641-01030). Connect the pressure feed tube to the PS gear. See «INSTALLATION»(ref-170954-S20417457752005012400000). Bleed the power steering system. See «REPLACEMENT»(ref-170954-S17588757932005012400000).

Scheme 10

Scheme 10: INSPECTION

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Check steering wheel freeplay : Stop the vehicle and face the tires straight ahead. Rock the steering wheel gently up and down with a finger lightly, check the steering wheel freeplay. Maximum freeplay: 30 mm (1. 18 in.) .
Check steering effort : Center the steering wheel. Remove the steering wheel pad. See step 1 under REMOVAL. Start the engine and run it at idle. NOTE: Take the tire type, pressure and contact surface into consideration before making your diagnosis. Measure the steering effort in both directions. Steering effort (Reference): 4.9 N.m (50 kgf.cm, 43 in..lbf) . Install the steering wheel set nut. Torque: 34 N.m (350 kgf.cm, 25 ft.lbf) . Install the steering wheel pad. See 14 in installation under STEERING COLUMN.

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Scheme 12: COMPONENTS

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Scheme 16: REMOVAL

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Remove steering wheel pad : Place the front wheels facing straight ahead. Remove the 2 steering wheel lower No. 2 covers. Using a torx socket wrench, loosen the 2 torx screws until the groove along the screw circumference catches on the screw case. WARNING: When storing the wheel pad, keep the upper surface of the pad facing upward. Never disassemble the wheel pad. When removing the wheel pad, take care not to pull the airbag wire harness. Pull out the wheel pad from the steering wheel and disconnect the airbag connector.
Remove steering wheel : Disconnect the connector. Remove the steering wheel set nut. Place matchmarks on the steering wheel and main shaft assembly. Using SST, remove the steering wheel. SST 09950-50013 (09951-05010, 09952-05010, 09953-05020, 09954-05021).
Remove front door scuff plate and cowl side trim .
Remove lower LH instrument finish panel : Disconnect the hood lock control cable. Remove the 2 bolts and lower LH instrument finish panel.
Remove the 2 bolts and lower LH instrument panel insert.
Remove column upper and lower covers : Remove the 3 screws and column lower cover. Remove the screw and column upper cover.
Remove combination switch with spiral cable : Disconnect the 3 connectors. Disconnect the airbag connector. Remove the 3 screws and combination switch with spiral cable.
Remove spiral cable .
Remove the clip and No. 2 heater to register duct .
Remove the 5 bolts and column hole cover .
Disconnect sliding yoke : Place matchmarks on the sliding yoke and control valve shaft. Loosen the bolt A and remove the bolt B.
Remove steering column assembly : Disconnect the connectors. Remove the 2 column assembly set bolts, nuts and steering column assembly.
Remove the bolt A and sliding yoke .

INSPECTION

Note. When using a vise, do not overtighten it.

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Scheme 20: INSPECTION

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Using a micrometer and caliper gauge, measure the oil clearance between vane pump shaft and bushing: Standard clearance: 0.03 - 0.05 mm (0.0012 - 0.0020 in.) . Maximum clearance: 0.07 mm (0.0028 in.) . If it is more than the maximum, replace the front housing and vane pump shaft.
Inspect vane pump rotor and vane plates : Using a micrometer, measure the height, thickness and length of the 10 vane plates. Minimum height: 8.6 mm (0.339 in.) . Minimum thickness: 1.397 mm (0.05500 in.) . Minimum length: 14.991 mm (0.59016 in.) . NOTE: HINT: There are 5 vane plate lengths corresponding to the following vane pump rotor and cam ring marks: Inscribed mark: 1, 2, 3, 4 or None . Using a feeler gauge, measure the clearance between the vane pump rotor groove and vane plate. Maximum clearance: 0.03 mm (0.0012 in.) . If it is more than the maximum, replace the vane plate and/or vane pump rotor with the one having the same mark stamped on the cam ring.
Inspect flow control valve : Coat the valve with power steering fluid and check that it falls smoothly into the valve hole by its own weight. NOTE: Install a new flow control valve with the same inscribed mark as the old one. Inscribed mark: A, B, C, D, E or F . Check the flow control valve for leakage. Close one of the holes and apply compressed air of 392 - 490 kPa (4 - 5 kgf/cm 2 , 57 - 71 psi) into the opposite side hole, and confirm that air does not come out from the end hole. If necessary, replace the flow control valve.
Inspect spring : Using vernier calipers, measure the free length of the spring. Minimum free length: 33.2 mm (1.307 in.) . If it is less than the minimum, replace the spring.