Toyota Auris 2013 Owner's Manual page 681

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 12-volt battery terminals may be disconnected.
 The 12-volt battery may be discharged. (P. 688)
Contact any authorized Toyota dealer or repairer, or another duly qualified
and equipped professional if the problem cannot be repaired, or if repair
procedures are unknown.
Emergency start function
When the hybrid system does not start, the following steps can be
used as an interim measure to start the hybrid system if the power
switch is functioning normally:
Set the parking brake.
1
Turn the power switch to ACCESSORY mode.
2
Press and hold the power switch for about 15 seconds while
3
depressing the brake pedal firmly.
Even if the hybrid system can be started using the above steps, the
system may be malfunctioning. Have the vehicle inspected by any
authorized Toyota dealer or repairer, or another duly qualified and
equipped professional.
UK_AURIS/AURIS_HV_EE (OM12F76E)
7-2. Steps to take in an emergency
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