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:

Symptom confirmation and diagnostic trouble code
HINT: The diagnostic system in the HIGHLANDER has various functions. The first function is the Diagnostic Trouble Code (DTC) check. A DTC is a code stored in the ECU memory whenever a malfunction in the signal circuits to the ECU occurs. In a DTC check, a previous malfunction's DTC ca ...