Hi all,

I’m new here (joined on Maria Munn’s recommendation) and hoping to tap into some collective experience!

I have a pair of Sea & Sea YS-01 Solis strobes. One is fully functional; the other has developed a fault that I’m trying to understand before deciding what to do next.

Observed behaviour on the faulty strobe:

• Powers up normally, LED red

• First TTL exposure: LED briefly goes green

• After that, the LED goes dark and stays off

• Strobe continues to fire reliably

• In manual, it fires consistently at all power levels

• In TTL, exposure is wildly inconsistent shot-to-shot (correct exposure → full dump → almost no output)

I’ve confirmed this with controlled side-by-side tests against the good YS-01 using identical settings, distance, and subject.

So I think what this means is:

• Flash tube / capacitor / triggering seem OK

• Manual output is fine

• TTL quench/control appears unstable or intermittent

• LED behaviour seems linked to the TTL state change

Questions:

1. Has anyone seen this specific YS-01 failure mode before?

2. Is this a known TTL control / quench circuit issue on older YS-01s?

3. Is repair realistically possible or economical, or is this effectively a “manual-only from now on” strobe?

4. If repair is possible, is it typically board-level or full module replacement?

The strobe hasn’t flooded, hasn’t been opened, and hasn’t been abused; this looks like a latent electronic fault rather than corrosion.

I’m trying to decide whether it’s worth pursuing repair, or whether experience suggests that replacement is the only sensible option.

Thanks in advance — any insight appreciated.

My next diving trip is T minus 26 days (Maldives) so I am a bit gutted to have found this issue in pre-trip checks, but hopefully time to solve it one way or another!

Chris

Edited 20 hours ago20 hr by Christopher Drye

When my YS-01 Solis died (different symptoms, no flashing), I investigated repairs. It was going to be a minimum of USD250 and involve mailing back to a repair facility in California or Japan. In the end I found it simpler to buy a gently used YS-01 (not Solis) for less money. Maybe if I lived in the same city / country as a repair facility my calculations would be different.

I guess Backscatter won't mind me sharing this response from 2024:

"Thank you for reaching out with this inquiry. We are a Sea&Sea

authorized repair center here at our shop in Monterey. If the issue

with the strobe is damage to the battery contacts and/or battery cap,

the typical cost to repair that issue is $215. If there is damage to

component(s) on the main circuitry assembly inside the strobe, parts

and labor to replace that circuitry costs $350. Once we evaluate the

equipment at our shop and determine exactly what is needed for the

repairs, we would send you a quote for that service. At that time you

can decide whether you wish to proceed with the service or reject

it. There is no cost for the evaluation itself. If you decided to pass

on the service, we could recycle the unit here at no cost to you or

can return it back to you for any reason at the cost of return

shipping."

The $250 figure was from the Sea&Sea Japan repair facility, but of course you have to get thing to Japan.

I have heard of many S&S strobes failing similar to this - the TTL circuit dies and can't quench the flash when required. It is possible it may spread to only full power on manual control.

I'd think that with 26 days to go, you would be pushing to get it repaired in the available time, unless there is a repair shop in country, but even then it will take to to assess and possibly get parts. Also given repair costs a new strobe might be the best solution. I would suggest researching what is available to buy now, if they have to get stock in, again time might be tight. Might be another Solis - or perhaps a pair on INON S220 - a nice little strobe and INON seem to have a better reliability reputation.

Thanks for the replies so far, I appreciate your help.

I'm really scratching my head now. Not quite sure what to do next, this failure and a massive drop in confidence in the YS-01's has thrown me a bit.

We do have a local (ish) "in country" repair / service centre here in the UK, however I called them this morning and the one guy that know about these strobes and their issues and he is not in until Wednesday. That in itself is also concerning (prone to failure, limited expertise) and from you info above almost certainly not economical or even possible to repair

So I think I have the following options given my next trip is 25 days away and I am trying to fit in a 1 day training course with Maria, using my intended equipment between now and the trip.

1) Do my training course and the next dive trip (17 -20 dives only) with a 1 strobe setup using the fully functional one in TTL mode

2) As above, but in Manual mode only (I read that TTL use can "wear out" the strobe more than manual use

3) Take both Strobes on the trip, but either use one TTL and the compromised one on manual, or both manual

4) Buy a new YS-01 Solis for £310 GBP and use on this one trip along with the other working one. When I get back sell all 3 of them as I can't be doing with this fragility and low confidence long term. then look with zero time pressure for a better solution (probably INON)

5) Buy 1x AOI Q1i to pair with the working YS-01. My budget could just about stretch to this, but I am confused on how the fibre optic connection would work (same connector style?) and also am mixing battery types AA vs 18650

6) Buy 2x AOI Q1i - I just don't think I can find £800 right now for 2 plus 4 18650s and the additional diffusers etc

7) Buy a single video light or hybrid strobe/video to pair with my working YS-01 Solis. Not sure on which one, the cost, and whether it has good/fast availability in the UK. I am open to new or good used condition, but again, time not on my side for this trip.

sorry for the long post, I've ended up in an unexpectedly complicated situation!

Edited 6 hours ago6 hr by Christopher Drye

UPDATE: I spoke to Maria and think I will go for option 4.

One thing with non matching strobes is it's not as straight forward to keep the lights balanced, also a video light is nowhere near as powerful as a strobe.

The other thing to consider is trying to use manual - it's not as hard as it seems. You don't say what setup you have, but if you are doing macro having the strobe at the same distance means the strobe exposure is constant. It's also easier to use a single strobe for macro. IF you end up buying one strobe I'd suggest the little INON S220, it also uses AA batteries and is an excellent little strobe.

If you want to balance the two strobes together one way you can try is have one strobe in TTL connected to your camera and the second strobe also in TTL can trigger off the flash from the first strobe. I expect it would trigger without a cable, but if you do use a cable run it off the first strobe. If I recall correctly the YS-01 have a port on front of the strobe for a trigger cable. The cable runs from the front of the strobe to the fibre port on the second strobe.

INON uses a screw on connection at the strobe end end but the camera end is the same as the YS-01.