You have a clock error. One of the interrupters is not breaking an opto, or has been making contact and has some cracked solder joints.

Sometimes the hands are not tight enough to the gears, and the minute hand does not break it's optos. I had to put another thin washer in mine before the clip.

It's a little pain in the ass that clock. I heard it was left out of FH because of this.

Nico - everything can be, also a cold solder joint. If it is so, the cold solder joint can only be at OPTO1. Look carefully at the 4 solder points on the back of the PCB, if the solder point are good.

BUT - I do not believe, that there is a cold solder joint.

Your problem is mysterious, I never heard of that.

What do the diagnostic LEDs on the board say, especially what does LED1 show, when the minute hand passes through OPTO1? It must go off, when the minute hand passes through. If it goes off, the fault is not on the board, but elsewhere "outside" the board. If it does not go off, the OPTO might be bad (it would be the first time for one of my boards), or the OPTO has bad contact in the socket (take the opto out 2 times and in again) or nethertheless a bad solder joint.

But I suppose, that there is some hardware-misalignment with your minute hand or the minute hand is worn out.

Please see this site:
http://pin-logic.com/tz_clock_fix.htm

Please keep me/us informed, the problem is "interesting".

-Ingo TZ-Clock_fault_Nico.JPG

I wonder if this is what happened to me... I've never had a clock issue, but after a game earlier this week I noticed the credit dot and test report said "clock is broken". I just did a quick clock test and it was fine after that, credit removed, attraction mode functioned perfectly, but haven't played it much since then.

For this reason, the diagnostic LEDs are there
Do not put in the resistor network the wrong way, the white dot on the resistor network (Pin1) MUST notch with the silkscreened 1 on the board (see instructions on my website)!!!!!!!

-Ingo

PS.:
Here is an excellent write-up, of "How to make Twilight Zone´s clock to work smooth without the "crappy" noise". See in the middle of the site.
http://www.pinballark.com/especial.html

Look on my website, go to TZ-Clock-PCB and then click on the french flag. There are at the end some (bad) fotos, of how the black hour interrupting wheel must be installed.

I googled a bit ... and yes, the cpu can be confused, if the big black hour hand gear
is not installed correctly. Look at the wonderful site of Dr. Ed Cheung and look for the following term "Reassembling the TZ clock gears":
http://www.edcheung.com/album/album08/pinball/tz.htm

-Ingo

Recheck on warping of the minute-hand.
Mine was slightly warped and registering when going clockwise, but skipped one on counter-clockwise (how apropriate

Hey Cogito,

I had a similar problem, but a bit different so I'm not sure if this will help. My clock tested and worked great, but usually after a few seconds into Clock Choas, it would freeze up and stop working.

Never got credit dot though, and upon the start of a new game, it would reset back to 12.00 and work fine for all other modes, until Clock Chaos started again.

I figured something was wrong with the reverse signal, and traced it down to that dreaded Z-connector. I would re-seat it, and the problem would go away for a couple days, then come back.

I finally removed the Z-connector and attached all those wires directly.

Not sure if that will solve your problem, but eliminating the Z fixed all the clock issues I was having.

Try to un-plug and re-plug both sides of it (the Z-connector) and see if the clock works then.

That damn Z was the cause of so many issues for me. Reboots, DMD distortions, the clock... Pin has run great since I got rid of it.

Good luck!

In the head, behind the back-glass (actually it sits right behind the DMD and speakers) in the lower left, there are two plastic molex connectors that plug into each other using the z-connector as a "bridge" between them. The connector looks like this:

http://www.pinballlife.com/index.php?p=product&id=2446

Its 7 pins (with one empty...only six wires connect..If i remember correctly), NOT 4 like the picture (just giving you a reference)

Might be difficult to notice at first because the two plugs attach on either side, but once you look closely, you'll find it.

Just unplug one side and re-connect it, then do the same on the other side.

The wires that run through there control the clock and DMD, and if loose cause all sorts of issues.

Fair warning, my problem was a little bit different, so I'm not sure if this will help you or not, but its an easy thing to test.

I can get the wire colors for you tonight when I get home if you cant find it.

Good luck!

Great machine, but a bear to work on. I've had a geneva switch error for months and since it doesn't effect gameplay, I refuse to take that damn gumball machine out again! I hate credit dot, but I'm learning to live with this one. lol

I couldn't get your link to open... but I am assuming it was my post you were referring to.

Backing up Cogito's desription... he has it down exactly. I have the same problem. I have different ROM's, but I haven't tried tem out... for me, being able to use coins is more important than whether the clock runs in Chaos... I know.. that sounds goofy even to me.

Hope you get it solved. I would love to have both!

That was me in the r.g.p. thread ...
Bad news, I sold the machine with the error. Meanwhile we bought an other TZ.

As I can remmeber, changing the ROM was not the final solution.
We changed the whole clock with an other and changed the clocks to different machines with no problem on the other machine but still the fault on mine . So at least it might be a ROM failure due a CPU will not break on this way. It was kind of a nightmare.

Good luck .. I am sure with Ingo "on board" you will figure out !

I spoke with a really great expert about your problem and he will look at it. So please stay a bit patient, we wil find the problems, that must be somwhere on the CP-Board.

-Ingo

I'll pitch in my thanks here as well.

Problem seems to be solved!!!!! - after more than 5 years!!!!!!!!!

A friend of mine in the UK had exactly the same problem.

The problem seems to be caused by a miswired switch in another location in the machine. In the case of my friend it was a miswired switch on the slot machine switch.

This is, what he wrote to me:
"... Just thought I would let you know, that I have now got a fully working clock
To cut a long story short (as I spent hours looking), somebody in the past had soldered the 2 wires on the slot machine switch on the wrong end of the diode swapped them round and the clock is perfect now. ...

I asked him the following:
"... How for hell did you find this fault? It is nearly impossible, to find such a disgusting fault. ..."

Here is his answer:
"... I found it by fluke really, I thought I would just test every playfield switch to see, if they all worked and by pure luck there was still a ball in the slot machine so that switch was on.
As I got to the "lite slot machine switch", I noticed that the right slingshot fired as I pressed the switch? After a quick look underneath at the 3 switches I noticed that the slot machine switch was wired wrong.
I swapped the wire to the correct side of the diode and that cured the slingshot fault and when I started a game and got clock chaos it was fixed

Thanks again for all your help ..."

I must not mention, that finding this fault, took many many weeks and hours of time.

Conclusion: If such a disgusting fault occurs with your clock in clock chaos, check ALL your switches in your machine for miswiring and/or a faulty or reverse connected diode on the switch.

I thought, this is a very important information to share with all of you for same future problems.

Tribute goes to GREAT BRITAIN, thanks my friend!!!!!

PS.:
Here is a photo of the switch (in the photo, it is now wired the correct way)

slot machine switch correct (resized).jpg