540 PCB Fault ??

I had a 540 go wrong, would flash but seemed to be out of sync with the camera and I got dark images. Nothing we did seemed to make a difference so we sent it off for repair and got this reply:

"I have had a look at the flashgun, The charge pcb is faulty, but the the whole PCB will have to be replaced, which can cost £150 plus Labour.
I have tried to order this part, but I have had no joy, and no delivery date. I feel it may be uneconomical to repair. Please let me know if you want me to send it back."

Anyone had the same problem?

Since sending that one off our other 540 has developed the same issue, any help would be much appreciated

Did you send it to Pentax to repair? That's a very odd reply "tried to order this part".
Is it still in warranty?

I have two of these with no problems so far.

To have two go the same way in a short time is odd are you sure it,s not the camera?
Is the camera sending to much trigger voltage to the flash, only a thourght mind

No we sent it to Asahi Photo Ltd as we wanted a quick turnaround and Pentax have always taken so long. There's no charge for the diagnosis and I'm definitely having it back from them so I could send it off somewhere else.

The problem didn't seem to be a charging issue though, so I'm wondering if it's been diagnosed correctly.

They are both out of warranty, maybe had them for 18 months/2 years. We use them a lot - maybe 2/3 weddings every week 1000 shots minimum each wedding maybe 1/3 - 1/2 of those with some flash. We have spares, a 400 & a 360 but having two go at the same time is not funny!

They are used on different cameras - initially on two K10s and more recently on two K20s, else I would agree with you. It does seem suss that they both go at the same [ish] time but maybe that's an age issue as they are both as old as each other.

Sounds like poor quality Chinese capacitors, loads of electrical stuff fails after 2-3 years because of them. I've got two Panasonic DVD recorders that are about 3 years old and showing signs of failing anytime now.

shim

If you are able to do so take a look at the capacitors like shim suggests. If it is built in a way that you can give it a go with a soldering iron it could very well be a cheap fix to this problem.

Sounds like they fall under the 'not fit for purpose' part of the sale of goods act, so you should get them repaired for free. You also have the EU 2 year consumer law to fall back on as well, so get onto your retail ASAP!

I would strongly recommend against that
Have you ever touched a flashgun capacitor before?? It's not funny at all

Take up the 2year EU consumer law
Matt

Seconded. Capacitors can be VERY nasty.

Very dangerous, potentially fatal. Don't do it unless you are experienced in handling electronic components.

A company I worked for many years ago made ionisation testing equipment used for testing the insulating properties of items like vehicle dristributor components. I used to test and calibrate the 'baby' ones at 10,000 volts and a shock from that soon woke you up.

A more experienced colleague dealt with the 'big boys' machine which generated 250,000 volts. Even having taken all the necessary safety precautions before, during, and after testing, all except grounding the main electrode to discharge the residual static after turning it off that is, he touched it and spent the next 20 minutes on the floor unconcious. He suffered no permanent harm.

Ok, yes you have to take precautions but when the capacitor is fully discharged there is no risk in handling them.
Just make sure that there is no residual charge left and there can't be a problem...

Got zapped by a sparkplug a couple of times and that is 30.000 volt. It itches a little but nothing more. The current is so low that the risk is quite low.
And yes, I know the voltage in a flashgun is rated at "high voltage" because it is over the 1500V DC low voltage limit (yes, everything below 1500V DC is considered low voltage)