EM TECH Stern Rawhide feature award

[ThePinballSpot]

Folks I am at my wits end and need another set of eyes on this issue. My Rawhide is awarding the feature when it shouldn't. So this game has features like extra bonus, extra ball, lites spinners and bumpers. The features alternate with various playfield switches. When you land in either of the 2 holes it scores the lit feature. Well mine goes beyond that and scores the lit feature any time the score motor runs. So if I hit a 500 or 5000 point target it scores the lit feature. Even after ball drain when the score motor runs to collect the bonus it scores the lit feature on the third bonus count. It is so bad that if the lit feature is double bonus it starts collecting single bonus for the first 2, then moves into collecting double bonus for the rest as the score motor scored the feature. I have checked, cleaned, adjusted and looked for shorted tabs on the following, outhole relay, score motor switches C1 and C2, feature change relay, 500 hole relay and both feature hole switches. Any help is appreciated.
Thanks, Todd

[John Robertson]

On 2021/09/08 9:05 a.m., ThePinballSpot wrote:
> Folks I am at my wits end and need another set of eyes on this issue. My Rawhide is awarding the feature when it shouldn't. So this game has features like extra bonus, extra ball, lites spinners and bumpers. The features alternate with various playfield switches. When you land in either of the 2 holes it scores the lit feature. Well mine goes beyond that and scores the lit feature any time the score motor runs. So if I hit a 500 or 5000 point target it scores the lit feature. Even after ball drain when the score motor runs to collect the bonus it scores the lit feature on the third bonus count. It is so bad that if the lit feature is double bonus it starts collecting single bonus for the first 2, then moves into collecting double bonus for the rest as the score motor scored the feature. I have checked, cleaned, adjusted and looked for shorted tabs on the following, outhole relay, score motor switches C1 and C2, feature change relay, 500 hole relay and both feature hole switches. Any help is appreciated.
> Thanks, Todd
>

Hi Todd,

One area to start with on Stern EM games are the wiper discs for the
bonus, ball count, etc. units. Often one of more traces has arced over
and made a carbon path to the next and you get random oddness happening.

Carve out any carbonized PCB you find - put shiny tape on the contact
face side of the PCB, then fill the hole with epoxy glue. The shiny tape
is to give you a smooth surface where the wiper runs over. Let it cure,
and see if the problem goes away.

If no arcing, then check the contacts on the suspect relay blades. Any
of the rivets showing carbon black on the side that doesn't contact
anything? That is indication of a loose rivet - solder or crimp it down
in place.

ChiCoin/Stern EMs are a bit of a pain...there are other tricks but that
is enough for now.

John :-#)#

--
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[ThePinballSpot]

Hi John,

Thank you for responding to my post. In this case the steppers are in excellent condition. I have owned this machine for many years and it was playing fine, other than being sluggish. It was very dirty and sooty on the bottom board, so I removed it and cleaned everything, including all steppers and all relay switches on the bottom board and the score motor switches that were easily accessible. So I caused this issue but have no idea as to how I did it. The cleaning did make the game play fast and snappy.

Todd

[John Robertson]

On 2021/09/08 3:06 p.m., ThePinballSpot wrote:
> On Wednesday, September 8, 2021 at 1:01:08 PM UTC-4, John Robertson wrote:
>> On 2021/09/08 9:05 a.m., ThePinballSpot wrote:
>>> Folks I am at my wits end and need another set of eyes on this issue. My Rawhide is awarding the feature when it shouldn't. So this game has features like extra bonus, extra ball, lites spinners and bumpers. The features alternate with various playfield switches. When you land in either of the 2 holes it scores the lit feature. Well mine goes beyond that and scores the lit feature any time the score motor runs. So if I hit a 500 or 5000 point target it scores the lit feature. Even after ball drain when the score motor runs to collect the bonus it scores the lit feature on the third bonus count. It is so bad that if the lit feature is double bonus it starts collecting single bonus for the first 2, then moves into collecting double bonus for the rest as the score motor scored the feature. I have checked, cleaned, adjusted and looked for shorted tabs on the following, outhole relay, score motor switches C1 and C2, feature change relay, 500 hole relay and both feature hole switches. Any help is appreciated.
>>> Thanks, Todd
>>>
>> Hi Todd,
>>
>> One area to start with on Stern EM games are the wiper discs for the
>> bonus, ball count, etc. units. Often one of more traces has arced over
>> and made a carbon path to the next and you get random oddness happening.
>>
>> Carve out any carbonized PCB you find - put shiny tape on the contact
>> face side of the PCB, then fill the hole with epoxy glue. The shiny tape
>> is to give you a smooth surface where the wiper runs over. Let it cure,
>> and see if the problem goes away.
>>
>> If no arcing, then check the contacts on the suspect relay blades. Any
>> of the rivets showing carbon black on the side that doesn't contact
>> anything? That is indication of a loose rivet - solder or crimp it down
>> in place.
>>
>> ChiCoin/Stern EMs are a bit of a pain...there are other tricks but that
>> is enough for now.
>>
>> John :-#)#
>>

> Hi John,
>
> Thank you for responding to my post. In this case the steppers are in excellent condition. I have owned this machine for many years and it was playing fine, other than being sluggish. It was very dirty and sooty on the bottom board, so I removed it and cleaned everything, including all steppers and all relay switches on the bottom board and the score motor switches that were easily accessible. So I caused this issue but have no idea as to how I did it. The cleaning did make the game play fast and snappy.
>
> Todd
>

Hi Todd,

If you unplugged anything to work on the game, check the pins of the
plugs, they used AMP plugs as I recall, not as reliable as the Jones
plugs the others all used. It isn't uncommon for a pin to be pushed
backwards and not make connection for these games.

Do you have the schematics, that always helps.

[ThePinballSpot]

Hi John,

That is a very good thought. Yes I did unplug many connectors to remove the playfield and bottom board. Perhaps one is not snug. I will check all of these plugs. Yes I have schematics and found the path of switches as mentioned in my first post but all checked out fine. I think it's gotta be one of those connectors because ive gone over and over all the bottom board relays and all looks fine. I will check all connectors and report back.

Thanks,
Todd

[ThePinballSpot]

Hi John, Reseating the plugs did nothing. I will go back to the schematics. I must be missing something. I know exactly what I am chasing. There are two ways to score a feature on the playfield, both kickout holes. And the running of the score motor has now become a third way to score a feature. So there doesn't seem to be a lot here. I will go have another look. The Rawhide schematics are not posted on IPDB but Stampede is up and they are the same.

Todd

[Mark]

On 9/8/21 4:06 PM, ThePinballSpot wrote:

> so I removed it and cleaned everything, including all steppers and all relay switches on the bottom board and the score motor switches that were easily accessible. So I caused this issue but have no idea as to how I did it.
>

A common mistake. Does the Bonus Collect relay fire when you get the
unwanted points? If you start the score motor by hand you you get
unwanted points?

One possibility is that the switch on the Bonus Collect relay that
connects maroon-yellow and blue-red wires (on the Stampede schematic) is
stuck closed or shorted. That would give you 2000 points for every 1/3
motor turn.

/Mark

[ThePinballSpot]

Hi Mark, It is not really a ''giving extra points'' issue. That is a byproduct that is caused by the issue at hand. I just gave the example of the end of bonus going into double bonus if that was the lit feature. It would have scored any lit feature including extra ball or lighting spinner or bumpers. I took a day off to relook at the schematics and give it more thought. So the features alternate with various playfield switches and the ONLY way to score the lit feature is by going into either of the two kickout holes. So any movement of the score motor like scoring 500 or 5000 points or collecting end of ball bonus scores the lit feature. I have gone through all associated relays many times. The only thought I now have is there may be a short within the two kickout hole switches. So tomorrow I am going to look in that direction and report back.

Thanks, Todd

[Mark]

So the issue is that one of the relays selected by the Feature Unit
(Spinner Re, Double Bonus Re, or Extra Re) fires when it shouldn't? If
you block the Motor C2 switch at D20 on the schematic does the problem
persist?

[ThePinballSpot]

Yes Mark, that is exactly the problem. I just tested blocking C2 and the problem is still there.

[Mark]

So when do the Spinner, Double Bonus or Extra relays fire? Or is one of
them always on? If there's a short around the Motor C-2 switch knowing
when the relays fire might help point to where it is. If one of them is
always on it could be that the Feature Unit common contact is shorted to
the green power rail somehow.

[ThePinballSpot]

That is a very good question Mark. They actually all start as off at the start of a ball as they should. I know this is a seldom seen game so I did a video to better describe the rules and what is going wrong. Thanks. Todd https://www.youtube.com/watch?v=EwIszpQ65HY

[Mark]

Here's another experiment but only if you know how to safely poke around
with the power on. Start a game, advance the feature unit to where you
could turn on the double bonus if you land in the hole. Then lift the
plafield and move the plug on the score motor service jack (front right
corner of the score motor) from the right socket to the left socket.
That will keep the motor from turning on its own.

At this point the game should incorrectly light the double bonus when
the motor turns. So watch the Double Bonus relay (2nd relay back in the
center of the bottom board) while you slowly turn the score motor cam
with your hand. If you do that a few times you should be able to figure
out which score motor switch or switch stack activates when the Double
Bonus relay fires. That might help find the problem.

[ThePinballSpot]

That experiment was very well Mark. I followed your instructions and found the entire C stack (as well as random switches in other stacks) closed when the double bonus relay engaged. So I started with the C stack by running further tests while blocking individual switches one at a time. I discovered that blocking C3 (ball index re lock) did not set off the double bonus relay.

[Mark]

Are you sure that blocking C3 stops the problem and not C2? C2 is green
to red-blue. C3 is green to red-black. They probably have their green
wire solder tabs connected together. It's harder to explain how C3
would be involved.

[ThePinballSpot]

Sorry Mark I just realized the schematics for Rawhide and Stampede are not exactly the same. Yes it is C3 and that score motor switch is the same as C2 on Stampede. Here is a link to proper Rawhide Schematics. https://pinside.com/pinball/forum/topic/score-motor-won-t-stop-start-relay-won-t-release-stern-rawhide#post-4848874

[Mark]

If blocking the motor C3 switch (on the Rawhide schematic) prevents the
Double Bonus or other feature relays from firing, it seems that there
must be a short around the feature hole switch and the parallel switch
on the 500 (hole?) relay. If you have a meter, what's the resistance
(not continuity) between the red-white and red-blue wires on either side
of those switches?

[ThePinballSpot]

Hi Mark. I find it much easier to explain and demonstrate through video. So here is a video. I did find a dead scoring switch in one of the kickout hole stacks. https://www.youtube.com/watch?v=NSvuO1SGpKw

[John Robertson]

The jumper you show is wrong, it shouldn't be there. Someone (lazy
tech!) added it to get the scoring to happen when the lower contact is
is activated, but I expect it has given an unintended consequence.
What appears to be happening is the top switch - scoring - isn't and as
it does score when the lower switch is closed and the jumper is to one
of the two blades of the scoring switch, therefore the other blade of
that scoring switch is not providing a path. I don't have the schematics
handy, but I would be carefully checking the scoring switch wiring!

[Mark]

I can't tell much from your video.

There are two switches under the feature holes:
- One switch at F32 on the schematic (green wire to white-red wire)
fires the Feature Hole relay.
- The other switch at C24 on the schematic (red-white wire to red-blue
wire) fires the Spinner, Double Bonus or Extra relay through the Feature
Unit, and motor switch C3.

I suspect you have a short across the second switch between red-white
and red-blue wires. I don't see why there should be a jumper across any
of the four solder tabs on the switch stacks under the Feature holes.
That might be the short. What two wires are jumpered together? If it's
green to red-white that would do it.

[ThePinballSpot]

I will list all the wire colours on the tabs of the switches from the bottom (fires the Spinner, Double Bonus or Extra relay through the Feature) up.
two red-white wires are on bottom tab.
blue-red wire is on next tab up. These switches are jumpered and the switch is dead.

red-white wire is third up and the top lug has two green wires attached. This top switch actuates both the kickout and scoring feature.

[Mark]

If red-white is jumpered to red-blue the switch is always closed and
your Double Bonus etc. relays will fire any time the score motor runs.

[ThePinballSpot]

Ok so I snipped the jumper and the problem is gone, but there is a new problem. The hole that had the jumper (lower hole) now only scores the points and does not award the lit feature. It looks like that is why a previous owner put the jumper in. What would cause this switch to become inoperable? Perhaps someone mixed up some same coloured wires on this switch stack as there are 3 red-white and 2 green wires.

[ThePinballSpot]

I just noticed that the second tab down has a white-orange wire. So it goes from the bottom tab up like this.
2 red-white wires to bottom tab.
blue-red wire to next tab up.
white-orange wire third tab up
2 green wires to top tab near playfield.

[Mark]

We know the wires to the switch are good because when they were jumpered
together the switch behaved as if it were stuck closed. So the problem
is in the switch. It could be dirty contacts, a bad connection between
the contact and switch leaf, cold solder joint, etc. You'll have to
experiment. Try shorting different parts of the switch together with a
small screw driver. Start with the lugs and work your way to the
contacts to see where it stops working.

[ThePinballSpot]

Your right Mark. When I short the tabs where the wires are connected it works. If I short anywhere else on the blades, including the tabs where the wires are, but not shorting the actual wire, I get nothing. And I can tell someone has done soldering on these wires, so it must be a cold solder joint. I will desolder the wires from both tabs and resolder them and that should do it. I will report back.

[ThePinballSpot]

This issue is a real pain. I now see why the previous owner just gave up and jumpered it. I can get it to work if I hold the switch contacts tightly together, like a jumper. But it wont work properly otherwise. I notice both contacts are rather worn, so I built a new switch to change one out and still not fixed. Unfortunately I am out of new contacts so I will have to build and replace the other switch in the future. The machine is playing great and I kinda like the challenge of only one hole awarding the feature. Many times it shoots from the lower hole and goes in the upper hole anyways. Thanks Mark for figuring out this problem.
Todd