BATTLE SPEEDLITE! PART UNO ( Speedlite 420EX Camera Flash )


Because I don’t have enough hobbies, and because apparently shopping for things is more fun than actually using them, I have taken up PHOTOGRAPHY! And because I am cheap, and hesitant about spending money, I limit my impulse spending to “great deals” and stuff I can “surely fix even if it IS broken”…

I purchased a first generation DSLR with some accessories at an auction. Enter the 420EX flash – surely a GREAT deal, until I got it home and it won’t power up.

STEP 1: Test the obvious shit

Step 2: Tool time!

Using my multimeter, I tested the batteries ( you know, just in case ). Placed the 4 batteries into the Speedlite Flash, and then checked to see if power was flowing between the two pairs of batteries. It was not. This suggested to me that there might be a broken connection inside the camera – I was pretty happy about this, because I can solder shit. A physically broken ( or corroded ) connection is probably in the realm of things I can fix.

Please ignore the voltage readings you see here. This is what I did, but the first time I did not get these readings.


Step 3: Breaking it Down

Started taking out screws, took me a while to find them all. 4 are hidden on the top of the flash, and you have to rotate it 90 degrees to see them. I very quickly stripped that top screw, but the others came out nicely.

IMG_8237-800My goal was to get inside, check the continuity of the battery connections, and hopefully narrow down the problem. When I opened it up nothing major fell out… but this time when I checked the voltage on the batteries… I got nice readings ( see top picture for reals this time ).

HEY I FIXED IT, I naively thought. Perhaps some wires were twisted, and I magically untwisted them, and lets go play with my new flash. I tried to put it back together again, and ran into these two little issues:



That thin plastic is supposed to slide between the board and the rotating part of the flash. For the life of me couldn’t get it back in. So I took it out. I’m guessing it might be important, but for now I don’t care.


To get the two halves back together I had to push down the rotate button on the back of the flash.. this raises a pin, and allows the pieces to snap back in place. It is conveniently labelled “PUSH”.

IMG_8232-800 IMG_8233-800

I didn’t put all the screws back in – just once screw in the bottom so the whole thing wouldn’t fall apart while I was holding it.


While the Speedlite 420EX flash would not power up on it’s own, I thought perhaps that this flash might only work on the camera. why? who knows, but I was feeling hopeful.

I went and plugged it on my camera, and of course nothing happened. Frustrated, about this time is when I actually READ the user manual I downloaded… looking for some secret answer to my problem. Perhaps there was just a switch I was missing.

It is worth noting that I took the entire thing apart, risked breaking it, and wasted a bunch of time BEFORE I even read the fucking manual. This is why I am pretty terrible at fixing things, and why every single victory in this blog is not just a victory against some horrible broken piece of trash, but against my own innate inability to Measure Twice and Cut Once.

So I RTFM’d and set all the switches, and nothing changed. Since I’m now in RTFM mode, I decide to download the SERVICE MANUAL and give it a read. Something important to note here… I could have really shocked the shit out myself. There is a capacitor that needs to be drained before working on this flash. And I guess there are like up to 100 volts that can sit around in it and shock the shit out of you.

So I learned a bit, and was preparing to go tear this thing apart again… but while playing with the rotation of the flash, suddenly it powered up. There may or mayn’t have been a crunching noise as it turned and then energized with an awesome whine.

Now the flash is not fully put together yet, so some wires are loosely held in place, and my initial thought is that some wire must have been pinched, or there was a short, or something that my monkey like banging has fixed. Not the most noble victory, but I’ll take it.

Tomorrow.. the exciting conclusion to BATTLE SPEEDLITE 420EX!

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