Canon Speedlite 430EX zoom issue

A good possibility is the zoom head is causing the clicking sound. As we zoom the flash, the inside of the head moves to the back and forward. Gently tap it a few times see if that helps. My guess is it needs servicing.

Check the diffuser is fully retracted. Pull it fully out then all the way back in.

Sunds like it's broken

Check the contacts on both the camer and the lens. I usually clean mine with methylated spirits or isopropyl alcohol. I have to do this every 3 months or so as dirt or even oils from your hands can stop the contacts from working properly.

http://www.usa.canon.com/cusa/support/consumer/eos_slr_camera_systems/flashes/speedlite_580ex/form_display/support_by_email

Use the above form for support by email for the canon speedlite 580ex TTL Flash.

Also, there is a phone number on the website.

http://www.usa.canon.com/cusa/support/consumer/eos_slr_camera_systems/flashes/speedlite_580ex#ServiceAndSupport

Your zoom motor is probably stuck. Remove the two screws on the front side of the tiltable head. Pry off the two tilt caps using a small flat head screwdriver (they are glued on). Remove the 4 screws found under each cap. Now you can separate the two sides of the head and take out the two lenses (remember exactly how the lenses were positioned). Try pushing the flash in or out (it should move with a little force). See if the flash now responds before reassembling.

This is where I found mine:
It's a 6 digit number located on the top half of the flash (the bit that tilts backwards and forwards). On one side it says Speedlite 430EX II, on the other side there are a few symbols and underneath is the serial number engraved on the plastic.
I also found it printed on the warranty card that came inside the box.

your flash has a diffusion panel in front, make sure its in all the way

good day
yitzy

Make sure it is not set to manual 'M' on the display. To get it to shoot in ETTL (Through the lens) press the mode button and it should read ETTL in the top left corner. This then means that the light is metered thorugh the lens and you are not relying on the manual settings.

Hope that helps. I had the same problem when i first got my.
By the way a brilliant all round bit of kit. I have traveled the world to some fairly extreme temps and got it wet (Rain, humidity, sea spray to deserts and serious dust) All good.

Good luck

I have a 430ex and S5, I don't think the zoom head will move without being mounted on a camera.

If the flash test fires ok, then it should be fine.