Toyota TUNDRA 2009 Manual page 570

5-2. Steps to take in an emergency
n The starter motor does not turn over, the interior lights and
headlights do not turn on, or the horn does not sound.
One of the following may be the cause of the problem.
l One or both of the battery terminals may be disconnected.
l The battery may be discharged. (→P. 581)
Contact your Toyota dealer if the problem cannot be repaired, or if
repair procedures are unknown.
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