How to use TTL on a PTTL camera and flash

Hi everyone. It's brain picking time.
An AF 500 FTZ on a now long gone K10 and K7. TTL no problem.
I still have the AF 500 FTZ.
An AF 540 FGZ on a k5iis & K3 PTTL no problem.
I have 2 AF 400 T hammerhead guns and I used to use them with sensors on previous cameras on TTL. With an AF 280 mounted on the camera.
However with PTTL the first flash sets off the hammerheads then of course they can't recharge to take the actual shot.
Question. How can I get my K5iis or my K3 to work on just TTL? I can't find anything in either my AF 540 FGZ handbook or my K 5iis handbook or my K3 handbook. I don't have a handbook for my (old) AF 500 FTZ flash. (If anybody has one or knows where to get one or download one) Let me know please.
I haven't tried my 500 FTZ on either camera or my AF 280 so I don't know if that would work. I'm reluctant to try without a little advice from someone who may just have that little bit more knowledge and experience.
For anyone reading this to whom I have given advice on flash it just shows we don't know it all and we all need a little help now and then.
CHEERS Vic.

Hi Vic
Basically I don't think you can anymore as unfortunately Pentax have taken away the flash sensors that ordinary TTL relied on and replaced it with P-TTL where it relies on a short pre-flash to set the metering. Having said that, I thought it had gone by the K-7 but you seem to have had it working?

I agree, AFAIK TTL is not available on P-TTL cameras. The flashes will fire, but exposures will be hit and miss. The best choice of mode for older flashes on modern DSLR's would be Auto (auto -thrystor) mode if available ... This needs the on-flash sensor of course. The beauty of it is that the flashgun is self sufficient in flash exposure terms, and it can be used on any DSLR.

Compensating the flash exposure is a little more tricky than with TTL, but its generally very reliable.

The only Pentax digital bodies that supported TTL were the *ist D and *ist DS.

The 500 FTZ on a P-TTL body shows TTL when you initially switch it on but reverts to M (manual) when fired then M shows all the time till you switch off and on again.

The 500 FTZ does not support A mode, the 500 FGZ does support A mode but does not follow the cameras ISO or Aperture or FL, you have to adjust these manually on the flash, however the Metz 58-2 is superb in A mode ( and not too bad in TTL)

Thanks folks. Sorry there. I made a little mistake. My 500 FTZ was used with my. Z1p, 645, & *istD. NOT my K7. I'm not sure about the K10???.
SO. It looks like if I want to set up my 2 AF400T guns to fire at the same time as the main flash (540FGZ OR Pop up) then I'll have to set up everything on manual. I have umbrellas and used to fire the 400T's through them like studio lights.
Ah well back to the drawing board as they say. I'll sort it out one way or another.
CHEERS Vic.