Toyota Highlander Service Manual: Power steering system

Power steering

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Precaution

1. HANDLING PRECAUTIONS FOR STEERING SYSTEM (a) Care must be taken when replacing parts. Incorrect replacement could affect the performance of the steering system and result in a driving hazard. ...

More about Toyota Highlander:

On-vehicle inspection
1. INSPECT BRAKE BOOSTER (a) Airtightness check.  Start the engine and stop it after 1 or 2 minutes. Depress the brake pedal several times slowly. HINT: If the pedal can be depressed (to the floor) the first time, but cannot be depressed as far on the 2nd or 3rd time, the boost ...