Toyota Highlander Service Manual: Lighting system

Lighting

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Precaution

1. PRECAUTION OF HEADLAMP BULB REPLACEMENT (a) If even a thin film of oil is left on the surface of the halogen lamp, the bulb may be damaged because the lamp will burn at a higher temperature. ( ...

More about Toyota Highlander:

On-vehicle inspection
1. CHECK THROTTLE BODY (a) 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 ...