Lexus IS350 AWD Owner's Manual page 571

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:
One or both of the battery terminals may be disconnected.
●
The battery may be discharged. (P. 575)
●
There may be a malfunction in the steering lock system.
●
Contact your Lexus dealer if the problem cannot be repaired, or if repair procedures
are unknown.
Emergency start function
When the engine does not start, the following steps can be used as an interim
measure to start the engine if the engine switch is functioning normally:
Set the parking brake.
1
Shift the shift lever to P.
2
Turn the engine switch to ACCESSORY mode.
3
Press and hold the engine switch for about 15 seconds while depressing the
4
brake pedal firmly.
Even if the engine can be started using the above steps, the system may be mal-
functioning. Have the vehicle inspected by your Lexus dealer.
IS350 AWD/IS350/IS300 AWD/IS300_U
8-2. Steps to take in an emergency
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