Canon EOS 700D Instruction Manual page 329

The built-in flash is raised by itself.
In the A, C, 2, 4, 6, and G modes, the built-in flash will be
raised automatically when flash is necessary.
The built-in flash does not fire.
If you shoot continuously with the built-in flash at short intervals, the
flash may stop operating to protect the flash unit.
The flash always fires at full output.
If you use a flash unit other than an EX-series Speedlite, the flash will
always be fired at full output (p.310).
Under [z1: Flash control] and [External flash C.Fn setting], if
[Flash metering mode] is set to [TTL], the flash will always fire at full
output (p.220).
I cannot set flash exposure compensation with external
flash function setting.
If flash exposure compensation has been set on an external Speedlite,
[Flash exposure compensation] (p.221) cannot be set in the
[External flash func. setting] screen. Also, if you set flash exposure
compensation with the camera and then set flash exposure
compensation with the external Speedlite, the Speedlite's flash
exposure compensation setting will be given priority. When the
Speedlite's flash exposure compensation is canceled (set to 0), [Flash
exposure compensation] can be set with the camera.
Troubleshooting Guide
329