2004 Toyota Tundra Owners Manual - Page 154
2004 Toyota Tundra Manual
Page 154 highlights
'04 TUNDRA_U (L/O 0309) If the indicator or buzzer comes on... Do this. Remove key. (o) Key reminder buzzer (p) Four −wheel drive system warning buzzer Shift the transfer mode correctly. 154 2004 TUNDRA from Sep. '03 Prod. (OM34426U)