Will not flash red/green

Pull it straight out from the body. See the instructions on page 9 of the manual.

New flashtube.

Hi Dave,
Try shorting out Center Pin to Outside Metal Contact after the light turned green. This must fire the flash.
If not, could be the flashtube /or trigger are defective.
Do you have a DVM?
[email protected]

Hi Larry,

Change all four batteries, I think one or more were not 1.25 or more voltages.

[email protected]

Sounds like something overheated and fried. I suppose you could take it apart to which part looks black.
Prolly needs a new circuit board and/or capacitor. Not sure what the repair cost would be, since it seems Vivitar is no longer in the flash business.
Best bet:
buy another 285HV on Ebay, either broken, for parts, or for replacing your dead one. Keep your old one fer parts.

Are you serious...you don't know how to turn it on? Ever wonder what the on/off switch is for?
Slide the switch from left to right and wait for the 'ready' light to change from red to green...then it's ready to shoot.

There is nothing wrong with your flash unit. The regular AA batters are 1.5 v volts each- if 4 batteries are used that is a total of 6 volts for proper operation. The rechargeable batteries are 1.2 volts each and 4 will get you 4.8 volts- thats 1.2 volts short and that is probably the root of our problem .

Try recharging you rechargeable batteries and put the im one more time- if the same problem happens you will have to stick with standard AA batteries. There external 6 volt packs that will work with your flash unit0 the are a bit of an expense at first but you will save on replacement batteries in the long run,.

Ed

omg, why did it fell? as we know that vivitar flash has so many little components in the inside, since its not really made "crash proof", you might have busted it already.

is the green light only turned on and not blinking?

Personally, I would not try it. While the Canon has a protection system built into the camera, the trigger voltage on the Vivitar is pretty high. I have had good results using a 283 on a slave shoe, you will have to stop down more with the extra light

Then I'd say it's a reasonably sure thing that the green light is just burned out, The lights are supposed to be off at first, then red when there's a partial charge, then green when there's a full charge, then flashing between red and green when the "battery saver" kicks in. If you're seeing off, then red, then off, then flashing red, then that means everything in the charging circuit is working perfectly, there's just no green light.