(Topic ID: 329786)

GTB one's and tens score reels not carring over

By durriti

1 year ago

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  • 21 posts
  • 6 Pinsiders participating
  • Latest reply 1 year ago by durriti
  • Topic is favorited by 1 Pinsider


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#1 1 year ago

Hello All,

l have a problem with the '1's' and '10's' score reels not carrying over, the '100's' carries over into the '1000's' ok. l've checked the ninth positions switches and 'zero' positions switches on both reels, they are clean and open/closed when they should be. All score reels reset correctly when the game button is activated.
Is this a score reel relay related problem?.


#2 1 year ago

What game? Depending on the specific game other switches are involved.

#3 1 year ago

Just for a quick trial, check (clean/adjust) the switches
in the 0 - 9 and 10 - 90 Score Relays..

#4 1 year ago

Its a Flipper Clown that seems to have had a hard life. l've checked and cleaned the switches, they have good contact when the relay is pressed with a finger, they all make good even contact. What l did notice is that the switch screws were loose, so they all have been tightened, but this has made no difference. l've attached a section of the schematic.
Thanks for your help.

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#5 1 year ago

You can’t check switches by sight. You need to check them using a meter. I don’t know how many times I’ve seen a switch look good, but not make electrical contact.

Try that on those switches in question.

#6 1 year ago

Can't you just jumper the "9TH. POS. UNITS UNIT" switch and score 1 pt repeatedly and see if the tens fires as well?

#7 1 year ago

l've just checked the 1 pnt and 10 pnt relays switches with a meter and are good. l've tried jumping the 9TH. POS. UNITS. UNIT, effectively cutting out the switch, (see picture) and tapping the 1 pnt. relay, 10 pnt. reel not being triggered. Am l miss understanding your direction?

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#8 1 year ago
Quoted from Billc479:

You can’t check switches by sight. You need to check them using a meter.

Sorry to disagree. I find Alligator clip jumper wires more reliable than a meter in most cases because the meter can get confused by electrical paths through other parts of the machine. Also a first check can be done by sight if you follow this guide:

For a switch to work 3 things are necessary:
1) When open, there should be a small space between the contact points (duh)
2) When closing, the long blade's contact point should push the short blade's contact point enough to move the short blade
3) The contact points should be clean, which they usually will be if #2 is happening

#9 1 year ago

Howard - I agree with you on using jumpers while troubleshooting. In this case, I was referring to the OP pushing the relay to see if the contacts closed. Since this seems to be the area where there's the trouble, I recommended using a meter to verify the contacts were closed. As we see later, OP did verify they were closing electrically.

I have had instances where the contacts appeared to be closed but had a film that prevented them from closing electrically. A quick swipe with a business card usually takes care of the problem. Like you said, usually this is not a problem if there's contact wipe.

For the OP, if whats being suggested being followed, I suspect an open wire.

#10 1 year ago

If you've jumpered (shorted) that switch correctly and the 10pt relay isn't firing, then as Billc479 said, you probably have a break in the wiring somewhere.

#11 1 year ago

l decided to move one of the aligator clips to other wire terminals on the 1 pnt. score reel and the tap the 1 pnt. relay. On the third terminal down from the top, the 1 pnt. bell sounds and score reel advances when the 1 pnt. relay is tapped, this continues until '0' on the units reel, and then the 10 pnt. reel advances once and 10pnt. bell sounds. What l appear to be joining is the green/black to brown/orange - one side of the 9th switch to the inside switch on the middle score reel cam. Second picture is with score reel and arrows pointing to what is being connected. Keep telling what l'm misssing.

Thanks again.

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#12 1 year ago

On the schematic snippet you posted, you're trying to jump the GR-BLK wire on one side of the "9TH. POS. UNITS UNIT" switch with the YEL-BL-RED wire on the other side of the same switch. Effectively, you're just shorting the switch, forcing it closed.

With that switch closed, every pulse from the N relay should fire the M relay....if everything's connected as it should be. That's assuming that N switch is good.

#13 1 year ago

Shorting the 9th switch and tapping the 1 pnt. relay does nothing only the third terminal down bring any result.

#14 1 year ago

You can use your jumper to bypass (short) lengths of wire also, in case there's a break in the wire. For example, you could hook one end directly to the lug of the M relay that's not connected to the black wire, and the other end of the jumper to the left (on the schematic) switch tab of the "9th. Pos. Units Unit" switch. Both those points should have the same color wire (YEL-BL-RED). If pressing the N relay with your finger then made the M relay fire, you'd know you have a break in the YEL-BL-RED wire somewhere in the length that you jumped.

#15 1 year ago

There's only 2 possible switches involved here and one is on the N relay. When the ninth position switch is closed and the N relay fires the M relay should fire. There could be an open/dirty switch on the N relay that's not closing, or the ninth position switch not closing (or both)

I don't see any wires in the posted photos that actually shows the correct ninth position switch jumpered.

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#16 1 year ago
Quoted from durriti:

Shorting the 9th switch and tapping the 1 pnt. relay does nothing

Instead of tapping the 0-9 Point Relay multiple times, put the
1's Score Reel on 9. Then elegater clip the front left set of contacts
on the 0-9 Point Relay. After doing that, the 10-90 Point Relay along with
the 10s Score Reel should be 100% energized not letting loose.
So now short the 1s 9th position switch, wiggle wires, do some jumping,
anything to get that 10-90 Relay to energize. As long as those
contacts are clipped and the 1's Score Reel is on 9, the 10s Score Reel
coil should be holding and buzzing..
I have a Flipper Clown, so I know it's the same with the 100s Score Reel.
Clipping the front left set of contacts on the 10-90 Point Relay while the 10s
Score Reel is on 9 (90) should energize and hold the 100-900 Point Relay,
which would hold in the 100s Score Reel coil..

#17 1 year ago

Firstly, thank you all for your input.

Paulace. Connecting/jumping the 'M' relay, non black wire to the 9th POS. switch either side and tapping the units relay didn't fire the tens score reel. Following the wires from the 9th POS. switch back to the 'N' relay, this seems to have no breaks. Wires being Gr/blk and bl/or. The 'N' relay has four switches, three can be seen on the section of schematic l posted, the forth is the 1.pnt. bell, further up the schematic. The 'N' relay, see picture 1, 1st switch front left, has the gr/blk and or/wh this has a diagonal link to the switch behind. Left switch behind has link and or/gr, (possibly bell). Right hand switch front wh/blk and wh/silver. Back righthand switch Or/bl wire (other 9th POS. wire) and wh/or pair -these are live. Jumping from the or/bu side of 9th POS. switch to the back righthand switch live wh/or pair fires 10pnt. relay, 10pnt score reel, 10pnt. bell and carrys over to the 100's at right point.

edednedy. Jumped from 'M' relay (non- black), to the or/bl - 9th POS. switch and tapped units relay but this fires 10pnt. relay, score reel and bell for each tap of the units relay, see picture, hopefully l have not miss understood what you asked. picture 2

Mopar. l clipped the lefthand front set of switches to various other switches but the only wire that causes the 10pnt relay, score reel and bell to lock on is the righthand back switch pair wh/or, (this is wire pair is live during the game but dead at game over) See picture 3 10pnt. relay locked on.

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#18 1 year ago

Hey durriti,
I don't have a schematic - what color is the vertical wire on the right side above the "Zero Pos. Balls to Play Unit" switch?

Just to make sure you understand the reasoning behind what we're doing here - the circuit that fires the M relay when the 1 pt. score reel is at 9 and you score 1 more pt. (N relay fires) is pretty simple: just 2 switches (N and 9th. Pos. Units Unit) and the M relay coil itself.

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What we're trying to do with the jumpers is short one or both switches, effectively taking them out of the circuit, or forcing them closed, if you prefer to think of it that way.

Putting one end of the jumper where the red X is (non-black wire on the M relay) and putting the other end where the yellow X is, should make the M relay fire. You're just bypassing both switches and connecting the M relay coil straight to the other side of the power bus. (This assumes that some switches along the right vertical wire on the schematic are closed as well. They should be, or none of your scoring relays would work.) If you do this, don't leave the jumper connected long - you'll burn up the M relay coil.

If the M relay doesn't fire when you do this, you have a problem with the M relay coil itself.

If you keep one end of the jumper at the red X and put the other end where the green X is (GR-BLK wire), you're shorting the "9th. Pos. Units Unit" switch. That switch is on the units score reel, though the GR-BLK wire runs elsewhere. Let's assume that your N relay switches are all working as they should, (which means that the N switch on the right side of the schematic snippet above closes when you either score 1 pt. or press the N relay armature closed with your finger.)

IF that's true that the N relay switches are working correctly, and you are jumpered between the red and green X's:

- if the M relay DOES fire when the N relay fires, the problem is in the switch (or wiring) that you jumpered...namely the "9th. Pos. Units Unit" switch.

- if the M relay DOES NOT fire when the N relay fires, the problem would be in the N relay switch, which you have not jumpered.

The problem could also be in the wiring between the switches, not the actual switches themselves. Look very carefully at all the solder tabs - hopefully, it's something you can see visually.

If not, you can use the jumper wire to "replace" the wire between switches. Go between one switch tab (in the back) and the next on the schematic - effectively replacing the original wire with your jumper.

The trick is making sure you're on the right tabs, switches or wires, especially with those old, faded wire colors. Also make sure your switch contacts are clean and sliding past each other slightly when closing. Looking good visually is no guarantee of an electrical connection, though - that's why we're using the jumpers.

#19 1 year ago

Hello Paulace,

The vertical wire that returns to the 'zero position' balls to play unit is red & white, (see posted section). As you write many wire colours have faded over time. l have noticed that there appears to be two wire gauges. l will be going through the area you suggest over the course of the next few evenings. Thanks again for the input.

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1 week later
#20 1 year ago

Hello Paulace,

Putting the jumper on the non-black wire on the 'M' relay and then going to each switch tab on the 'N' relay switch stacks, only one switch tab caused the 'M' relay to pulse and activate the tens score reel, see picture. The tens relay will lock on if maintain contact. The red arrow points to what l now believe to be red/white pair of wires that are main, (bus?) return. On the schematic it doesn't show what colour it is but l think l'm talking about the 'N' switch, (position 8 - H on the schematic, the section you posted).

Leaving the jumper on the non-black 'tens' relay wire and attaching to the GR/BLK wire at either the score reel or the 'N' switch, (one's unit), and tapping the units relay doesn't activate the tens relay no matter how times l tap the units relay.

At this point it needs to be said that the units, tens relays work when prompted by jumper wires, all of the score reels coils also work when pulsed by a relay or carry over (hundreds to thousands only)

In an attempt to figure out which wire/switch is faulty l did this. l attached a jumper on the non-BLK wire on 'units' relay and then touched the other end of the jumper to the red/wh return, (on units relay). This caused the units relay/score reel/bell to pulse, and tapping several times caused the tens unit relay and score reel to pulse at the correct cary over point. l think this jumps from the non-BLK wire on 'N' relay to the otherside BL/RED wire on the ADDS UNITS UNIT, it completes a circuit but l can't firgure which wires are involved.

l did the same thing again on the tens ('M'), relay, attaching the jumper to the non-blk wire and tapping the RED/WH return wire on the 'M' relay, this caused the relay/bell/score reel to pulse, continuing to tap caused the hundreds relay/score reel to activate at the correct point. Again l think this jumps from the non-BLK wire on the 'M' relay to the otherside of the OR/RED wire on the ADD TENS UNIT, and again l can't firgure which circuit it completes.

l've identifed what each switch fuction is on both the units/tens relays. Looking straight at the relays, left back switch on both units/tens relays are the units/tens bells. Those circuit work with BLK wire to oneside of coil, other side of coil to relay switch, when the relay pulses switch closes completing ciruit to RED/WH (return).
On the units front left switch pair,is GR/BLK 9th pos. the other side RED & WH (return)(this switch has a link back to the unit bell).
On the units right front switch pair, it has a wire that loops back to the non-BLK wire on the units relay, the other side goes to the units lockin switch on the units score reel.
And on the units right back switch pair, is BL & RED - add units unit, and the other side is RED & WH (return).
On the 'Tens' (M) relay
Lefthand front switch pair, OR-BLK 9th pos. otherside RED & WH (return)(this switch has link back to tens bell).
Right hand front switch pair, BR-BLK to lock-in switch (score reel), other side loops back onto non-BLK wire on tens ('M') relay.
Righthand back switch pair, OR-RED to ADD TENS UNIT, other side to RED/WH (return)

Where l am now,
l've unpicked parts of the loom catgut to trace wires but have found nothing what appears to be broken etc and lost the 1 point scoring via the 1 point switches on the playfield...

Any thoughts would help.

Thanks again.

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1 week later
#21 1 year ago

Well l don't what l've done but the 'carry over' problem is resolved, 1 pnt. scoring restored. The still has some other issues but as it stands it resets correctly and only the roto target, tilt and add-a-ball scoring adjustment have faults, these will be looked at very soon, thanks for the input.

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