Toyota TUNDRA 2009 Manual page 182

2-1. Driving procedures
n Gear range display when driving in S mode
The current gear range is displayed on the combination meter. (→P. 181)
n When driving with the cruise control system (if equipped)
The engine brake will not operate in the S mode, even when downshifting to
5 or 4 (6-speed models) or 4 or 3 (5-speed models). (→P. 214)
If the shift lever cannot be shifted from P
n
→P. 577
n If the S indicator does not come on even after shifting the shift lever to
S
This may indicate a malfunction in the automatic transmission system. Have
the vehicle inspected by your Toyota dealer, immediately.
(In this situation, the vehicle will operate as if the shift lever is in D.)
n AI-SHIFT
The AI-SHIFT automatically shifts the gear to the optimal position according
to the driver performance and driving conditions.
The AI-SHIFT automatically operates when the shift lever is in the D posi-
tion. (Shifting the shift lever to the S position cancels the function.)
Downshifting restrictions warning buzzer (in the S mode)
n
To help ensure safety and driving performance, downshifting operation may
sometimes be restricted. In some circumstances, downshifting may not be
possible even when the shift lever is operated. (The warning buzzer will
sound twice.)
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