Canon 420EX - Manual (Page 48)

Troubleshooting Guide
The flash does not
fire
The batteries are exhausted
► Install new batteries
{->
page 10)
Batteries are installed incorrectly
► Install the batteries in the proper orientation. {-> page 10)
The 420EX's mounting foot is not securely mounted on the camera's hot
shoe
► Slide the mounting foot all the way into the hot shoe (-> page 12)
The camera’s hot shoe contacts or the 420EX's contacts are dirty
► Clean the contacts
The power turns off
automatically.
The 420EX has not been used for 90 sec
► Press the shutter button halfway
► Press the test firing button. page 15)
The 420EX cannot be
detached from the camera
The locking collar has not been loosened enough
*■
Loosen the locking collar until the locking pin disengages (-> page 12)
The subject looks
blurred in the
picture
If flash is used in the < Av > mode under low-light conditions, a slow sync
speed is set automatically A blurred picture is prone to occur if the
camera is handheld at a slow sync speed.
*• Use a tripod. page 22, 36)
*• Set the camera to the < P > mode page 18, 32)
With high-speed sync,
the picture came out
underexposed. With high-speed sync, the Guide No changes depending on the sync
speed The faster the sync speed, the shorter the effective flash range will
become
► Check the Guide No. before taking the picture. (-> page 50)
The slave unit does
not fire
The slave unit’s wireless selector is set to <OFF>
*• Set the wireless selector to <SLAVE>. page 13)
The slave unit is not within the master unit's wireless transmission range
► Position the slave unit within the master unit’s wireless transmission
range.
The slave unit's wireless sensor does not face the master unit
*• Point the slave unit's wireless sensor toward the master unit page
44)
The master unit's flash mode is set to <M> or < M ulti >
► Set the master unit's flash mode to < E-TTL > page 43)
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