My Scared Stiff has no power

Hello,

My Scared Stiff won’t power up. No lights, no sound and no signs of life. It was working fine about 3 months ago and I haven’t moved or touched it since then.

I’ve checked all the fuses. There’s power to the on/off switch and when turned on there’s power to the transformer at the back. I’m not sure what to do next. From reading other posts I hear transformers rarely fail.

Please can you help me, I’m quite new to pinball and this is the first problem I can't solve on my own! Are there some basic tests I can do to isolate the issue?

Jon

#2 10 years ago

YZF

yzfguy

Pinside+ Frequent

12y 146K 11,174 7

Anything change since last time it worked? Any recent repairs or mods done?

#3 10 years ago

FAZ

pinball_faz

Pinside member

Chicago Burbs, IL

13y 99,300 2,735 5 32

Check for the lights on the Power Driver board and the CPU board.

Check voltage at each of the test points.

faz

#4 10 years ago

SYM

Sympathy

Pinside member

Quoted from yzfguy:
Anything change since last time it worked? Any recent repairs or mods done?

Nothing. It's been sat in the corner of my office untouched since it last worked.

#5 10 years ago

SYM

Sympathy

Pinside member

Quoted from pinball_faz:
Check for the lights on the Power Driver board and the CPU board.
Check voltage at each of the test points.
faz

There're no lights on the boards. I'm not sure where the voltage test points are. I'll see if my manual has them marked...

#6 10 years ago

DAV

wayout440

Pinside member

You have a DMM/or voltmeter?

Know how to use it?

#7 10 years ago

RobertWinter

Pinside+ Frequent

12y 117K 2,302 2

With the power off, reseat all the connectors on the transformer. Completely unplug them, then reconnect firmly.

I would also reseat all the power connectors on the CPU board.

#8 10 years ago

DAV

wayout440

Pinside member

Some things to note that may give clues:

Line Fuse: Located in the metal power box just inside the coin door, if one of the driver board diodes D19-22 is blown, this fuse can fail immediately at power up. Also if the varistor inside the metal power box is shorted, this fuse will blow. And finally, if a bridge rectifier on the AV board is blown, this can also cause the line fuse to blow on some games (but only when the coin door is closed!)

Do you have any lights at all?

Note:
As a WPC game is powered on, the GI lamps do not come on until the CPU board has fully booted and initialized the game (except on WPC-95 games, where two of the five GI lamp strings are not triac controlled; they come on immediately as the game is powered on.

#9 10 years ago

SYM

Sympathy

Pinside member

Quoted from wayout440:
Some things to note that may give clues:
Line Fuse: Located in the metal power box just inside the coin door, if one of the driver board diodes D19-22 is blown, this fuse can fail immediately at power up. Also if the varistor inside the metal power box is shorted, this fuse will blow. And finally, if a bridge rectifier on the AV board is blown, this can also cause the line fuse to blow on some games (but only when the coin door is closed!)
Do you have any lights at all?
Note:
As a WPC game is powered on, the GI lamps do not come on until the CPU board has fully booted and initialized the game (except on WPC-95 games, where two of the five GI lamp strings are not triac controlled; they come on immediately as the game is powered on.

Thanks, yes I've double checked the fuse in the switch box by the coin door. I have a voltmeter and know how to take basic measurements, but I'm unsure where I should be testing. No lights at all. Not on the playfield or any of the boards.

#10 10 years ago

FAZ

pinball_faz

Pinside member

Chicago Burbs, IL

13y 99,300 2,735 5 32

Perhaps you should check some basics first.

Can you validate that you have power to the outlet? Perhaps a GFCI in the string popped, breaker.

Also, the power cord is like a PC. Modular plug that plugs into the back of the machine. Not hardwired. Make sure that did not pull loose.
faz

#11 10 years ago

FAZ

pinball_faz

Pinside member

Chicago Burbs, IL

13y 99,300 2,735 5 32

OP
Quoted from Sympathy:
I have a voltmeter and know how to take basic measurements, but I'm unsure where I should be testing

Start where the power comes in and chase it through the driver board. If there's no lights on the driver/CPU board, it must be very early in the circuit.
faz

#12 10 years ago

SYM

Sympathy

Pinside member

Quoted from RobertWinter:
With the power off, reseat all the connectors on the transformer. Completely unplug them, then reconnect firmly.
I would also reseat all the power connectors on the CPU board.

I've now tried unplugging and reconnecting the white connectors highlighted in green, but no luck. I notice a lot of tape either side of the transformer. Is this normal? Should I be able to remove the cables in the area highlighted in red?

Transformer.jpg

#13 10 years ago

DAV

wayout440

Pinside member

The tape is fine, look at your last pic, the green circle on your right. Thats the feed in, to the primary side of the transformer. You may be able to take measurements with the plug still put together if your probes are sharp enough to get down into the connector to reach the metal contacts. What you want to do is see if you have any AC getting into the transformer at all. Meter on A/C. Please be careful, you are dealing with line voltages. See if you have any A/C voltage here.

Pins 1-9 (BLACK - ORANGE) is one main primary winding
Pins 3 - 7 or 8 (White/Black stripe - either White/Orange Stripe) is the other primary wiring.

#14 10 years ago

SYM

Sympathy

Pinside member

Quoted from wayout440:
The tape is fine, look at your last pic, the green circle on your right. Thats the feed in, to the primary side of the transformer. You may be able to take measurements with the plug still put together if your probes are sharp enough to get down into the connector to reach the metal contacts. What you want to do is see if you have any AC getting into the transformer at all. Meter on A/C. Please be careful, you are dealing with line voltages. See if you have any A/C voltage here.
Pins 1-9 (BLACK - ORANGE) is one main primary winding
Pins 3 - 7 or 8 (White/Black stripe - either White/Orange Stripe) is the other primary wiring.

Great, I've just tested and yes I've got A/C voltage here! So when I switch on I've got power to the transformer. The only D/C voltage I can measure on the CPU board though is across the battery holder...

#15 10 years ago

DAV

wayout440

Pinside member

Don't worry about the CPU just yet...

There are a lot of connections coming off the secondary of the transformer to separate boards, are you absolutely certain that no LED indicators are lighting up on the power driver board?

Between the secondary (output) of the transformer is a big 12 pin connector, this feeds multiple voltages to the A/V and power driver board, it does not feed anything to the CPU board.

The 50VAC and 20VAC secondary outputs are also protected with an interlock switch between the secondary and the 12 pin connector.

> Check for approximately 100VAC at pins 3&4 of J605 on the A/V board, that will tell you if anything is making it out of the secondary of the transformer to the A/V board. 100VAC for display power does not go through the 12 pin connector.

> Check J129 pin 1&2 pair of red wires going into the power driver board for approximately 9 VAC. If this is not there, you will not be able to get your +5VDC to run the CPU board.

#16 10 years ago

SYM

Sympathy

Pinside member

Quoted from wayout440:
Don't worry about the CPU just yet...
There are a lot of connections coming off the secondary of the transformer to separate boards, are you absolutely certain that no LED indicators are lighting up on the power driver board?
Between the secondary (output) of the transformer is a big 12 pin connector, this feeds multiple voltages to the A/V and power driver board, it does not feed anything to the CPU board.
The 50VAC and 20VAC secondary outputs are also protected with an interlock switch between the secondary and the 12 pin connector.
> Check for approximately 100VAC at pins 3&4 of J605 on the A/V board, that will tell you if anything is making it out of the secondary of the transformer to the A/V board. 100VAC for display power does not go through the 12 pin connector.
> Check J129 pin 1&2 pair of red wires going into the power driver board for approximately 9 VAC. If this is not there, you will not be able to get your +5VDC to run the CPU board.

I've checked these pins on the A/V board and power driver board and there's no A/C voltage. None of the LED indicators light up either.

#17 10 years ago

ZAZ

zaza

Pinside+ Frequent

10y 92,650 3,268

Is it correct that you live in the UK and the machine is working on 220-240 Vac ?
Can you make a picture of the plug, located behind the coin-door, right above the main-switch ?
And can you do a continuity-test by pulling the plug from the outlet and measure for resistance through the entire primary coil by measuring the ac-in pins with the main switch on ?

I know it is rare but when you measure voltage at the primary side of the transformer, it is still not 100% sure that the windings are connected.

#18 9 years ago

SYM

Sympathy

Pinside member

Here's a picture of the switch box. Yes I'm in the UK with 240VAC mains, the fuse in the bottom left is also 240V. To measure the voltage at the primary side of the transformer which of the wires I've marked should I be measuring across?

Switch box.jpg

#19 9 years ago

MJS

schudel5

Pinside member

20y 166K 6,392 27

Sounds like a connector or fuse issue.

#20 9 years ago

RUS

RussMyers

Pinside member

Linwood, NJ

12y 76,550 2,882 7

Open the power box (unplugged game) completely and let's have a good look at the stuff inside.

RussMyers

#21 9 years ago

TRP

fuseholder

Pinside+ Frequent

12y 97,800 909 70

Open the power box, check the thermistor to the to the RF filter. Or see repair #818 on the pinball ninja repar site. It might just be this problem, he fixed.

#22 9 years ago

BOB

0geist0

Pinside member

Royal Palm Beach, FL

14y 60,050 1,778 4

Something I learned not too long ago if the batteries are bad in a WPC 95 the security board will not boot up. Check that first. Could be an easy fix.

#23 9 years ago

RUS

RussMyers

Pinside member

Linwood, NJ

12y 76,550 2,882 7

Quoted from fuseholder:
Open the power box, check the thermistor to the to the RF filter. Or see repair #818 on the pinball ninja repar site. It might just be this problem, he fixed.

That's exactly the kind of thing I'm looking for inside the power box.

#24 9 years ago

ZAZ

zaza

Pinside+ Frequent

10y 92,650 3,268

OP
Quoted from Sympathy:
There’s power to the on/off switch and when turned on there’s power to the transformer at the back.

I see no reason to open the power box.

The reason why I asked for this picture is to show where to measure and to see how it is plugged.
In blue circle, between pin(1,2) and pin(7,8) with main switch on, you will have 240Vac.
But when jumper between pin(9) and pin(3) is loose/broken (green circle), the transformer will not work.
When working correctly, you will also measure 120Vac between pin(1,2) and pin(9).
With mains disconnected, you can also measure for continuity.

Let's start with this information

trafo1.JPG

#25 9 years ago

NAT

NathanP

Pinside member

Lenexa, KS

12y 45,150 986 11 8

I guess its not really 'stiff' then is it?

#26 9 years ago

CBM

spfxted

Pinside member

Saddle River, NJ

12y 147K 24,659 4 9

thats what she said.jpg

#27 9 years ago

SYM

Sympathy

Pinside member

Quoted from 0geist0:
Something I learned not too long ago if the batteries are bad in a WPC 95 the security board will not boot up. Check that first. Could be an easy fix.

I tried this one. Always hoping for an easy fix

#28 9 years ago

SYM

Sympathy

Pinside member

Quoted from zaza:
I see no reason to open the power box.
The reason why I asked for this picture is to show where to measure and to see how it is plugged.
In blue circle, between pin(1,2) and pin(7,8) with main switch on, you will have 240Vac.
But when jumper between pin(9) and pin(3) is loose/broken (green circle), the transformer will not work.
When working correctly, you will also measure 120Vac between pin(1,2) and pin(9).
With mains disconnected, you can also measure for continuity.
Let's start with this information

Thanks for your help zaza. I'm only measuring 0.2v here when I switch on

Can I plug my mains directly into the socket on top of the switch box to bypass the cables from the back?

#29 9 years ago

SYM

Sympathy

Pinside member

I think I've found the problem! I briefly heard a slight electrical crackling sound near the transformer in my last test. I removed the protective coating from the mains in and found burnt wires on the AC safety capacitor. I'm going to try replacing it:

safety capacitor.JPG

#30 9 years ago

ZAZ

zaza

Pinside+ Frequent

10y 92,650 3,268

OP
Quoted from Sympathy:
Can I plug my mains directly into the socket on top of the switch box to bypass the cables from the back?

I have to say NO, although this socket is an Exit, with some hacking, it is possible, but don't.
It is easier to make some measurements and find where you're losing power or continuity, and it looks like you found something.
Is this the the line-filter you opened ?

#31 9 years ago

SYM

Sympathy

Pinside member