WPC-89 Coindoor buttons not working.

I recently purchased a non-working Black Rose that when turned on would display the typical factory reset display, but the coindoor control buttons were nonfunctional and could not get beyond that point. The batteries on the CPU had leaked with damage to components below it. Parts were literally falling off the board. I purchased a replacement CPU from Pinball Basement and transferred the U4, U6 and U9 chips as required. These chips did not appear to be damaged by the alkaline leak, or anywhere close to the leak. With the new board installed, I still had the same problem where the coindoor buttons would not work.
I checked and there is no short at the buttons due to bending or a loose screw, etc.
I tried shorting the switches at the coindoor with no response.
I disconnected J205 and tried shorting the pins for those switches with no luck.

The last couple times I turned the game on the screen now says check Fuses 114 and 115 (power driver board). The fuses test fine with a DMM, out of the game. The coindoor buttons still don't work.
BR1 on the power driver board tests ok.
I disconnected and reconnected the molex at the transformer.
No change.

Any help and suggestions would be appreciated.
Thanks

#2 2 years ago

TOX

ChrisHibler

Chris' Pinball Repair

Chesterfield, MO

12y 120K 9,997 46

Check F114/F115 can be caused by lack of 12V power.
Measure the 12VR power at the power/driver board test point.

--
Chris Hibler - CARGPB #31
http://www.ChrisHiblerPinball.com/Contact
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#3 2 years ago

???

pins4u

Pinside apprentice

Your new MPU comes from a source KNOWN to supply non or partly working boards.

I certainly wouldn't trust it.

#4 2 years ago

BCE

pindoc1

Pinside+ Frequent

Quoted from pins4u:
Your new MPU comes from a source KNOWN to supply non or partly working boards.
I certainly wouldn't trust it.

Thanks for the advice. I will keep that in mind, but it is unusual that it is the exact same symptoms as the original board.

#5 2 years ago

BCE

pindoc1

Pinside+ Frequent

Quoted from ChrisHibler:
Check F114/F115 can be caused by lack of 12V power.
Measure the 12VR power at the power/driver board test point.
--
Chris Hibler - CARGPB #31
http://www.ChrisHiblerPinball.com/Contact
http://www.PinWiki.com - The Place to go for Pinball Repair Info

Thank you. I will check into it.
Any thoughts on the coindoor buttons?

#6 2 years ago

???

pins4u

Pinside apprentice

OP
Quoted from pindoc1:
Thank you. I will check into it.
Any thoughts on the coindoor buttons?

Coindoor switches are 'direct' switches. They go via LM339's direct to the system NOT into the sw matrix.

I would suspect the plugs where they connect to the MPU - easy to test - just locate the connector (left side one from memory but check) unplug the wires to the coin door and take the pins to ground to prove the MPU is working or not.

#7 2 years ago

TOX

ChrisHibler

Chris' Pinball Repair

Chesterfield, MO

12y 120K 9,997 46

https://www.pinwiki.com/wiki/index.php/Williams_WPC#Check_fuses_F114_and_F115_message
--
Chris Hibler - CARGPB #31
http://www.ChrisHiblerPinball.com/Contact
http://www.PinWiki.com - The Place to go for Pinball Repair Info

#8 2 years ago

???

PinRetail

Pinside+ Addict

Unknown

2y 47,050 1,870

You replaced the cpu with extensive acid damage, but did you replace the connectors on the bottom of the CPU board?

If there is corrosion that looks green or fuzzy they will need to be replaced.

#9 2 years ago

FJB

ibuypinballs

Pinside+ Frequent

11y 88,300 1,262

I just went thru this on a Getaway. I had the same message on the DMD to check fuses F114 & F115. I had no 12 volts on the driver board. The D2 diode was no good. Here is a diagram of the 12 volt circuit.

pasted_image (resized).png

#10 2 years ago

BCE

pindoc1

Pinside+ Frequent

Quoted from PinRetail:
You replaced the cpu with extensive acid damage, but did you replace the connectors on the bottom of the CPU board?
If there is corrosion that looks green or fuzzy they will need to be replaced.

The alkaline did not make it to the connectors. The pins on the original board are clean. The connectors look clean. Thank you.

#11 2 years ago

KJO

eyeamred2u

Pinside+ Frequent

Cleveland, OH

7y 74,800 2,857 5

OP
Quoted from pindoc1:
The alkaline did not make it to the connectors. The pins on the original board are clean. The connectors look clean. Thank you.

What do you mean "look" clean? Did you remove them and inspect each one? Just an honest question, cuz I have been on many a service calls back in the day where I heard that same line, but when I pulled the wire from the housing I saw corrosion. The silent/invisible killer if its not green but sometimes soft white

#12 2 years ago

BCE

pindoc1

Pinside+ Frequent

Update: I followed the trouble-shooting guide and found a lost connection between the voltage regulator and the C2 capacitor. I pulled the C2 and it had leaked. Just cleaned up the leak and waiting for the board to dry. Then I'll replace the capacitor and jumper a wire between the regulator and the positive lead of the capacitor. Hope this solves the problems including the coindoor buttons, but I have my doubts about that.

#13 2 years ago

BCE

pindoc1

Pinside+ Frequent

Quoted from eyeamred2u:
What do you mean "look" clean? Did you remove them and inspect each one? Just an honest question, cuz I have been on many a service calls back in the day where I heard that same line, but when I pulled the wire from the housing I saw corrosion. The silent/invisible killer if its not green but sometimes soft white

Thank you. I will keep that in mind.
However, when I grounded the pins for the switches on the new circuit board with the connector off the board, it did not work either. So, I am thinking it is something else.

#14 2 years ago

KJO

eyeamred2u

Pinside+ Frequent

Cleveland, OH

7y 74,800 2,857 5

OP
Quoted from pindoc1:
Thank you. I will keep that in mind.
However, when I grounded the pins for the switches on the new circuit board with the connector off the board, it did not work either. So, I am thinking it is something else.

Good update, keep us posted.

#15 2 years ago

???

PinRetail

Pinside+ Addict

Unknown

2y 47,050 1,870

Nice find about a bad C2!

But let's talk about switches on the WPC 89 board.

On your CPU, J205 in the bottom left corner. This is a 12 pin connector and has orange wires going to it.

Pin 12 is on the left side, and pin 1 is closest to the middle of the board.

Dedicated switches work by having ground connected to them.

I use an alligator clip and I clip to a screw head.

Pull all the connectors from the bottom of the CPU board.

Now you have nothing connected to the switch inputs.

Take your alligator clip and touch it to the exposed pin on J205 in position 12. This is the leftmost pin.

Nothing happens.

Touch it to the pin directly right of pin 12, this would be pin 11.

Nothing happens.

Keep moving it over, one by one.

At pin 9, you should enter into the menu.

Pin 9 is the 4th pin from the left hand side of the connector.

If you cannot get into the menu by touching the correct pin on J105 to ground, you have a board problem.

If it easily goes into the menu, you have a problem with the plug at J105, the wire, or you have problems at the coin door board in the bottom of the game, or you have problems with the switch not activating.

You can plug the connectors on the bottom of the CPU back in.

Note! Do not try to touch a grounded wire to J206, 207, 208, or 209! You can blow things up!

In order to troubleshoot your switch problems we first have to make SURE That the CPU is working properly. If you can ground pin 9 on J105 and get into the menu then your problem is not on the CPU, it's further down the list of things connected to J105.

Hope this helps!

#16 2 years ago

BTF

PinballManiac40

Pinside+ Frequent

14y 234K 17,632 104

OP
Quoted from pindoc1:
Thank you. I will keep that in mind.
However, when I grounded the pins for the switches on the new circuit board with the connector off the board, it did not work either. So, I am thinking it is something else.

No 12volts=no switches will register. Confident that C2 was your problem.

#17 2 years ago

???

pins4u

Pinside apprentice

Quoted from PinballManiac40:
No 12volts=no switches will register. Confident that C2 was your problem.

Yes, the 12V supplied to the MPU ONLY runs the LM339 comparators - these interface the switches to the processor - so yes, no 12V means NONE of the inputs on the MPU will work.

The lesson here is simple. When you have a problem, ANY problem, start by confirming ALL voltages are present and correct. Without all voltages present and correct the machine CAN NOT function correctly.

ALWAYS start EVERY repair by confirming voltages!

#18 2 years ago

BCE

pindoc1

Pinside+ Frequent

Update - Almost Resolved.
Since I had the driver board out and had one bad, leaking capacitor, I decided to check the others. My DMM decided it didn't want to work in capacitance mode or the cap's were all just really bad so I replaced all the larger 30 year old capacitors. No other capacitor leakage found. I put the board back in and the CPU would not boot and had no lit led's on the CPU. On the driver board, I had all the voltages correct now except for 5v - nothing. The 12v measured good with a DMM and by the LED. Pulled the board again, reflowed the new capacitor for 5v, replaced the 5v voltage regulator (Q1) and checked all the bridge rectifiers and fuses on the board, which all were good. Still no 5v and no CPU activity at all.
So I swapped in the driver board from my White Water and the game booted right up. The coindoor buttons now work great so that was likely the 12v problem, as was suggested above.

But somehow I buggered up the 5v on the original driver board. Any suggestions before I take the driver board to be looked at professionally?

Thanks to everyone for the help.

#19 2 years ago

BCE

pindoc1

Pinside+ Frequent

Quoted from pins4u:
Yes, the 12V supplied to the MPU ONLY runs the LM339 comparators - these interface the switches to the processor - so yes, no 12V means NONE of the inputs on the MPU will work.
The lesson here is simple. When you have a problem, ANY problem, start by confirming ALL voltages are present and correct. Without all voltages present and correct the machine CAN NOT function correctly.
ALWAYS start EVERY repair by confirming voltages!

I will add that to my "Always check the fuses first!" mantra.
Thank you.

#20 2 years ago

???

pins4u

Pinside apprentice

You have very likely pulled some/all of the 'vias' from the holes in the board when you replaced the caps. The vias connect the top copper to the bottom usually though holes where parts are mounted.

These old boards are VERY delicate and it is super easy to damage them like this.

You will have to meter out each and every track coming from the caps you replaced. Check top AND bottom and use a jumper wire to repair the continuity when you find the broken connection.

Another thing to add to your repair list is "shotgunning parts RARELY fixes any problem!" Locate the EXACT issue and fix that FIRST before replacing other parts willy-nilly. This just makes things harder to fault find as you can potentially introduce additional faults.

#21 2 years ago

FNG

DumbAss

Pinside+ Frequent

9y 109K 2,984

Quoted from PinballManiac40:
No 12volts=no switches will register.

Which is why I put a redundant LED on my CPU board indicating +12VR. This has actually saved me a few times on the bench when I plugged my power supply into only +5V/GND instead of the +12V/+5V/GND connector.

12v_led.jpg

OP
Quoted from pindoc1:
so I replaced all the larger 30 year old capacitors.

OP
Quoted from pindoc1:
But somehow I buggered up the 5v on the original driver board.

Quoted from pins4u:
You have very likely pulled some/all of the 'vias' from the holes in the board when you replaced the caps. The vias connect the top copper to the bottom usually though holes where parts are mounted.

Odds on favorite that you ripped the through hole at the positive lead of C5. This is where the positive output of BR2 goes from the top of the board to the bottom of the board and then to Q1. Check for continuity between the positive output of BR2 and the positive lead of C5.

Quoted from pins4u:
Another thing to add to your repair list is "shotgunning parts RARELY fixes any problem!"

Agree 100% with this. I have fixed many boards that have been shotgun "repaired".

#22 2 years ago

KJO

eyeamred2u

Pinside+ Frequent

Cleveland, OH

7y 74,800 2,857 5

Quoted from DumbAss:
Which is why I put a redundant LED on my CPU board indicating +12VR. This has actually saved me a few times on the bench when I plugged my power supply into only +5V/GND instead of the +12V/+5V/GND connector.
[quoted image]

Odds on favorite that you ripped the through hole at the positive lead of C5. This is where the positive output of BR2 goes from the top of the board to the bottom of the board and then to Q1. Check for continuity between the positive output of BR2 and the positive lead of C5.

Agree 100% with this. I have fixed many boards that have been shotgun "repaired".

This added feature is a lifesaver when I do board work on WPC's. This is why I have to recommend your boards.

#23 2 years ago

BCE

pindoc1

Pinside+ Frequent

UPDATE - SOLVED:
I removed C5 and restored the connection at the via and reinstalled the capacitor. Double checked the continuity with BR2 and Q1, which all checked good. Reinstalled the board and it all now works!
Now on to cleaning, replacing bulbs and rubber rings.

I learn more from my mistakes and subsequent success than from an initial success.
Plus, I learned that if 12v is out, the coindoor switches won't work, and if 5v is out the CPU won't work.

It is great advice to not to try to solve a problem by a shotgun approach. But just to be clear, I was not shotgunning to solve the problem by replacing all the caps. I was trying to perform preventative maintenance while I had the board out.
But I forgot the rules:
1. If it ain't broke, don't fix it.
2. The enemy of good is better.
But I screwed up, learned some lessons and was able to repair it. =)

Thank you to everyone for the help.

#24 2 years ago

BCE

pindoc1

Pinside+ Frequent