Flash doesn't communicate with camera via TTL Cord

I just bought a cheap TTL cord off BHPhoto for my 580EX II and the flash wouldn't communicate with the camera. It will still fire, but only at full strength in TTL mode. The flash doesn't know what aperture the camera using, nor can it meter. The flash works perfectly with the cord otherwise.

It's a brand new cord, but the flash is used. Anybody encounter this before?

yes, did you by any chance get the dot3 cord? I had all sorts of trouble with it using my 580exII. It worked fine with my 430ex. I think the locking mechanism on the 580exII interfered with the cord.

gonzogolf wrote in post #11989812
yes, did you by any chance get the dot3 cord? I had all sorts of trouble with it using my 580exII. It worked fine with my 430ex. I think the locking mechanism on the 580exII interfered with the cord.

Its Pearlstone. It works now, continuously for 20+ shots. I just stretch it a little in random directions and they suddenly start talking. I wonder if I should be concerned about this. After the all, the shipping one way will be about the half the price as the cord.

Spoke too soon, it is a intermittent problem.

This will sound like a strange kind of comfort for your problem cord!...

I have a Canon OC-E2 cord (purchased new, now about 7 yrs. old) for my 40D and Metz 54MZ. Randomly the cord will lose connectivity between the flash and camera...the flash and camera still communicate for the flash to choose ETTL mode (over TTL mode), it will continue to trigger, but the flash will overexpose by outputting full power. This happens much more if the camera is in Portrait orientation, but it does happen in Landscape orientation once in a while.

So I bought a new Canon OC-E3 cord, thinking the OC-E2 had gone bad. Same problem.
So I obtained two different aftermarket new cords thru POTN's member, FlashZebra. Same problem.
FlashZebra very nicely took back the cords, since they did not fix my problem. And I sold the OC-E3 on POTN since even a newer model Canon genuine cord had the same issue!!! But the problem NEVER occurs when the flash is mounted directly on the camera hotshoe!

Based upon the fact that many others have suffered similar issues even with Canon cords, I lay blame on some aspect of the fundamental Canon design of flash communication...why else would flash work correctly when directly on the hotshoe, but not work reliably even with a Canon cord?! Some folks have even asked Canon, but they get a non-answer.

Wilt wrote in post #11990007
This will sound like a strange kind of comfort for your problem cord!...

I have a Canon OC-E2 cord (purchased new, now about 7 yrs. old) for my 40D and Metz 54MZ. Randomly the cord will lose connectivity between the flash and camera...the flash and camera still communicate for the flash to choose ETTL mode (over TTL mode), it will continue to trigger, but the flash will overexpose by outputting full power. This happens much more if the camera is in Portrait orientation, but it does happen in Landscape orientation once in a while.

So I bought a new Canon OC-E3 cord, thinking the OC-E2 had gone bad. Same problem.
So I obtained two different aftermarket new cords thru POTN's member, FlashZebra. Same problem.
FlashZebra very nicely took back the cords, since they did not fix my problem. And I sold the OC-E3 on POTN since even a newer model Canon genuine cord had the same issue!!! But the problem NEVER occurs when the flash is mounted directly on the camera hotshoe!

Based upon the fact that many others have suffered similar issues even with Canon cords, I lay blame on some aspect of the fundamental Canon design of flash communication...why else would flash work correctly when directly on the hotshoe, but not work reliably even with a Canon cord?! Some folks have even asked Canon, but they get a non-answer.

This is actually strangely comforting. I now figured out the trick. I must make sure the flash sits in the connector real good before I lock it down. I was able to replicate the problem by putting the flash in the cord more or less carelessly, like I would mount it on the camera. As soon as a I remount the flash on the cord carefully, problems went away.

Glad my tale of woe managed to help you resolve your problem to some degree.

Don't get me started on ODF chords.

That's OCF chords.

windpig wrote in post #11990496
Don't get me started on ODF chords.

It sounds like your engine is already revving high, and you are waiting for the 'Christmas tree' to change color, before you drop the clutch and lay down some rubber!

Wilt wrote in post #11990515
It sounds like your engine is already revving high, and you are waiting for the 'Christmas tree' to change color, before you drop the clutch and lay down some rubber!

I'm so old, I can't even type anymore

I've just bought a Canon G12, Vivitar DF-483-CAN flash, and Vivitar cord VIV-FC-CAN. Everything is brand new.

With the flash directly in the hotshoe it seems to work fine(though about 2/3 stop overexposed for my taste)
With the extension cord the in-camera flash is disabled but the flash does not fire (in any mode), or show indication of control of the flash or match zoom setting. nothing.

I have checked with a multimeter that there are no shorts in the cable. The four small contacts show continuity and the larger contact at the top shows an open circuit. From what i can decipher from various searches, the large contact is unused.

I bought this flash to have a master w/less control unit without the size and weight of the Canon Speedlite 580EX II Flash.

I thought maybe the G12 had small but significant changes to firmware that hinders full compatibility with off-brand flashes.

I was about to spring for the original cable OE-C3, but with the Vivitar cord in hand and looking at the magnified OE-C3 image on the Canon website they are the same unit. ( all markings, line-up and construction of flex-guard).

I live in the Caribbean and the cost of these items start at 50% more than the US. I thought i was making good choice by going with Vivitar. The Nissin and Sigma flashes have too many reports of failure for my comfort.

I was beginning to love the G12, but this tread has me seriously wanting to return all and build a kit with another brand.

AbleTech wrote in post #11990905
IWith the extension cord the in-camera flash is disabled but the flash does not fire (in any mode), or show indication of control of the flash or match zoom setting. nothing.

I have checked with a multimeter that there are no shorts in the cable. The four small contacts show continuity and the larger contact at the top shows an open circuit. From what i can decipher from various searches, the large contact is unused.

The 4 small contacts are for 'communication' between the camera and flash. The large contact, and the contact at the edge of the hotfoot on the flash, are for flash trigger...the large contact definitely needs connectivity or the flash would never fire.

I would either return the Vivitar card to the store for exchange, or find out how to go about getting replacement under warranty.

Thank You Wilt!
I woke up just to check for replies. Will go for exchange.
Guess i had my blinkers on cause i think of Vivitar as a "brand" name. The 35mm gear never gave me any trouble.

Will sleep better now
Thanks again
Tony

Given a choice I would chose a cord specifically advertised as an E-TTL cord over one advertised as just TTL. It shouldn't make a difference with these cords, but with some products it does actually matter. Better safe than sorry.

http://www.bhphotovide​o.com …Camera_E_TTL_II​_Shoe.html

I just checked my own genuine OC-E2 cord and discovered it is not simple straight-thru connectivity on the center (large) pin of the cord!!!

If you use the Diode test mode of the VOM, with Positive lead on the flash shoe (female) end and the Negative lead on the camera hot foot (male) end of the cord, there is connectivity shown. With Negative lead on the flash shoe (female) end and the Positive lead on the camera hot foot (male) end of the cord, there is NO connectivity shown.

If you simply use Resistance mode (typical for connectivity) of the test meter, with Positive lead on the flash shoe (female) end and the Negative lead on the camera hot foot (male) end of the cord, there is connectivity shown only momentarily before showing NO connectivity; reverse the polarity of the test leads and NO connectivity is ever shown.