Toyota 2009 Tundra Owner's Manual page 598

5-2. Steps to take in an emergency
The starter motor does not turn over, the interior lights and
n
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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