System 11 guru's unite! Road Kings oddities, please help **FIXED!**

Hello, ive been lurking a little bit, found many answers along the way, but now im against the wall, and need some more specific help.

My Tools available:
Dmm
Logic Probe
Soilder station

As of the time of this post:

Visual inspection of all play field wiring to all coils confirmed and verified to be in good condition.

Ohm test of all coils verifies all are in good useable conditions and within spec.

All fuses removed and tested with dmm for continuity

All transistors/predrivers tested on diode setting while board removed from game, found to be within expected specs.
and each transistor tested for continuity to ground from tab to board ground while removed from game, and none are found to be faulty or have shorted.

Current issues:

During game play:
Jet bumpers do not work
Flippers do not work
Kickers do not work

Ball feed, and kickout work

Lock coil for ramp pulses 15 times at power up, during attract mode, and then during game play each time a ball drains.

Test mode:
testing coils returns same results, no jets, kickers, or flippers.

Shorting transistor tab to ground with jumper, pops all the non working solenoids

My expectations:

Please ask specific questions, ( for example dmm, diode mode, Q79 black to center, red to each outer leg = ? & ?)

Walk me through what youd like to know and I will test and respond. I can send / post pics/vid

[Im pretty handy, and pretty good at following instructions.]

Thanks in advance.

Post last edited 10 months ago: “Flip flopped a few things”

#2 10 months ago

GMK

grantopia

Pinside member

I went to check your FB post people were helping on and it looks like it was deleted. If you haven't checked your voltage at the coils and power supply like several people suggested you are going to be chasing ghosts for a bit.

#3 10 months ago

C_U

Definitive

Pinside member

Thanks for all your help grant, I have followed those suggestions, and checked voltages which I found to match the schematics. I should have posted those results in my intro.

As a side thought though,
I cant see those voltages at the coils being an issue as the coils fire when I short the transistor tabs.

#4 10 months ago

GMK

grantopia

Pinside member

http://techniek.flipperwinkel.nl/wms11/index1.htm#trans

I would start taking a look at the solenoid A/C relay next before the mpu:

(This page will give you step by step instructions better than I can summarize)

Section 3b will walk you through it. A bit down from there there is another section around testing the under playfield relays. Take a look at these and see if anything helps. I didnt get to see that video you posted more than once but it looked like the one relay under the pf was constantly firing.

#5 10 months ago

BKB

the96stang

Pinside member

Enfield, CT

9y 90,850 2,494 70 13 1

Double check your connectors. Mainly the one on the top right of the MPU. Very easy to plug that one in wrong.

#6 10 months ago

DEC

GRUMPY

Pinside member

Most likely, U-50, 55 or 56 is bad. Do you have a logic probe?

#7 10 months ago

C_U

Definitive

Pinside member

Hey Grumpy.

I do have a probe. I can poke around if you can guide me

#8 10 months ago

DEC

GRUMPY

Pinside member

Do you know what a NOR chip and HEX inverter chip are?

#9 10 months ago

DEC

GRUMPY

Pinside member

When you start a game the processor chip sends out an enable signal which then activates the special solenoids and flippers. The enable along with the blanking signal is what turns on all the coils and relays. Both of these signals come together at U-50.
5 (resized).PNG

#10 10 months ago

DEC

GRUMPY

Pinside member

Once you connect you probe you will need to start a game and then test pins 11 and 12 of U-50. Both need to be low, then check the output on pin 13, it should be high.
pasted_image (resized).png

#11 10 months ago

DEC

GRUMPY

Pinside member

If this is good then move to the input of U-56 pin 5, it should be the same as the output of U-50 pin 13 a high. Then check the output of U-56 pin 6. Since this is an inverting hex buffer chip, the output should be a low.

pasted_image (resized).png

#12 10 months ago

DEC

GRUMPY

Pinside member

If that test good this brings us back to U-50 again. The output of U-56 pin 6 is connected the the inputs of U-50 at pins 8 and 9. Both of these inputs should be low as they are tied together, And since a NOR chip is also a inverter chip the output on pin 10 should be a high. Now since your special solenoids are not working during a game but work in coil test you are not getting the low signal from U-56 pin 6. Either U-56 is bad or there is a broken trace between U-56 pin 6 and U-50 pins 8 and 9. Let me know what you find.

#13 10 months ago

GMK

grantopia

Pinside member

Quoted from GRUMPY:
If that test good this brings us back to U-50 again. The output of U-56 pin 6 is connected the the inputs of U-50 at pins 8 and 9. Both of these inputs should be low as they are tied together, And since a NOR chip is also a inverter chip the output on pin 10 should be a high. Now since your special solenoids are not working during a game but work in coil test you are not getting the low signal from U-56 pin 6. Either U-56 is bad or there is a broken trace between U-56 pin 6 and U-50 pins 8 and 9. Let me know what you find.

I don't know if impacts the testing but it sounds like his coils are not working in test either (Test mode: testing coils returns same results, no jets, kickers, or flippers.).

#14 10 months ago

DEC

GRUMPY

Pinside member

Quoted from grantopia:
(Test mode: testing coils returns same results, no jets, kickers, or flippers.).

If the flipper were to work but not the special solenoids this would lend itself to a U-49 issue. But since he grounded the transistor tabs and the coils worked but the flippers don't, this will be a enable issue. When the game is placed in coil test the enable should be turned on and then the pia chips fire the coils. Since controlled coils are firing but not special coils the blanking signal is good but not the enable. So I'm going to stick with U-50,55 or 56 is bad.

#15 10 months ago

GMK

grantopia

Pinside member

Quoted from GRUMPY:
If the flipper were to work but not the special solenoids this would lend itself to a U-49 issue. But since he grounded the transistor tabs and the coils worked but the flippers don't, this will be a enable issue. When the game is placed in coil test the enable should be turned on and then the pia chips fire the coils. Since controlled coils are firing but not special coils the blanking signal is good but not the enable. So I'm going to stick with U-50,55 or 56 is bad.

I follow. And I didn't mean to imply you weren't on the right track with the suspicion, just didn't know if you saw that part of his post and if it was relevant. The logic makes sense.

#16 10 months ago

DEC

GRUMPY

Pinside member

Quoted from grantopia:
And I didn't mean to imply you weren't on the right track with the suspicion,

No I didn't take it that way. That's why forums are great, a bunch of nice people trying to help others out looking for nothing in return.

#17 10 months ago

RDM

boscokid

Pinside member

Wilmington, DE

6y 64,050 933 4

Grumpy teaching another graduate level course in component level troubleshooting!

#18 10 months ago

DEC

GRUMPY

Pinside member

https://www.ispot.tv/ad/7oMF/holiday-inn-express-the-solution

Quoted from boscokid:
Grumpy teaching another graduate level course in component level troubleshooting!

Maybe not!

#19 10 months ago

C_U

Definitive

Pinside member

Okay, results are in:

Testing 7402 @ u50:
Pin 11 - no reading
Pin 12 - low
Pin 13 - low

I continued even though results were not as desired

Testing 7406@ u56

Pin 5 - low
Pin 6 - high

I selected different connection points for my probe and repeated the same tests, results remain the same.

#20 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
Pin 11 - no reading
Pin 12 - low
Pin 13 - low

Since this is a NOR chip you need both inputs to be low to get a high output. Pin 11 is the enable input coming from the PIA chip U-10. Did you start a game before this test? Has anyone replaced U-50 in the past? Can you check the output of U-10 pin 19 after starting a game, what do you get?

#21 10 months ago

C_U

Definitive

Pinside member

Yup game was started for testing.

U10 pin 19 yields high in attract, low in game

#22 10 months ago

C_U

Definitive

Pinside member

all of the mentioned chips are socketed. Including u10

Can we pull them and test legs?

#23 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
U10 pin 19 yields high in attract, low in game

OK somehow this low in game signal is not getting to U-50 pin 11. There must be a bad trace or poor solder joint some where.

#24 10 months ago

C_U

Definitive

Pinside member

Is U10 pin 19 a direct run to u50 pin 11? Without interruption?

#25 10 months ago

DEC

GRUMPY

Pinside member

I think it is time to pull the CPU board out and do a continuity test from the U-50 chip lead pin 11 to the via point on the bottom of the board under U-49. This will confirm if the U-50 socket and socket solder joint are good to the bottom of the board. If that's good then you will need to test the U-10 socket.

#26 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
Without interruption?

Yes, but is not a very direct way. It will change from the top to the bottom of the board and maybe back to the top again.

#27 10 months ago

DEC

GRUMPY

Pinside member

I suppose this maybe a good time to ask if you are capable of this type of repair. If not you can ship it off now with a note of the problem and it would be an easy fix for a pro. If you are then post a good pic of the back of the board so everyone can what you are up against.

#28 10 months ago

C_U

Definitive

Pinside member

Well if my tracing traces skills are correct....

15832700600377953751996601001336.jpg

#29 10 months ago

C_U

Definitive

Pinside member

Honestly, i doubt im skilled for type of repair, but I feel i am capable with the right direction. I definitely dont mind spending the money to have it done for me, but thats not how I got into pins lol. 100% no bs only bought the 1st 1 because it was broken and i wanted to learn how to fix it.

So if you dont mind continuing to point me where i need to go, im all in.

#30 10 months ago

C_U

Definitive

Pinside member

Trace replaced

15832712951449026389173075439290.jpg

#31 10 months ago

C_U

Definitive

Pinside member

I know its not pretty, but it works, now the test results are as you described

U50:
pin 11 low
Pin 12 low
Pin 13 high

U56:
Pin 5 high
Pin 6 low

Is it bad that the trace for u10 pin 19 went threw that blob of soilder and the + of the battery tray? Could that have caused problems further into u50?

By the way:

Flippers are back and function properly.
Kickers now work properly
Left jet bumper works
Ramp works

What i do not have now is top, right or bottom jet, ball save or the solenoid where the ramp drops the ball in the left side.

Additionally I noticed the relay under the playfield (under shooter lane) pulses non stop during game mode

Post last edited 10 months ago: “Added info”

#32 10 months ago

DOZ

dozer1

Pinside member

Sargeant, MN

7y 99,200 1,375 17

Good find. Looks like who ever melted out the battery holder toasted the trace.

#33 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
I know its not pretty, but it works, now the test results are as you described

You should be go to go.

Playball!!

#34 10 months ago

C_U

Definitive

Pinside member

Well not so fast lol i added info to that post in an edit

#35 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
What i do not have now is top, right or bottom jet, ball save or the solenoid where the ramp drops the ball in the left side.

Additionally I noticed the relay under the playfield (under shooter lane) pulses non stop during game mode

I'm stuck at work till midnight, will look this over when I get home.

#36 10 months ago

C_U

Definitive

Pinside member

Youre awesome. Thank you!

#37 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
What i do not have now is top, right or bottom jet

Solenoids 19,21 and 22. OK. Do they pulse in coil test?

OP
Quoted from Definitive:
ball save or the solenoid where the ramp drops the ball in the left side.

Solenoid 6 Power kicker left outlane. Do you hear a relay clicking in coil test?

OP
Quoted from Definitive:
Additionally I noticed the relay under the playfield (under shooter lane) pulses non stop during game mode

Find this relay and tell me what color stripe is on the brown wire.

pasted_image (resized).png

#38 10 months ago

C_U

Definitive

Pinside member

That relay has Brown with White stripe. ( this is Also the relay that pulses non stop in game mode)

But im Headed back under the playfield now... during coil test the F2 SS fuse popped, im now showing continuity to ground on 3J3-6 Red wire, White stripe, (sheet shows vio/blu not accurate). Regardless, with connector unplugged this wire in particular shows contact to ground.

I cannot help but think power from the battery tray made its way down the damaged trace to the chips on either side, (U10 pin 19 and U50 pin 11). Both had continuity to the blob when I located it.

I have bypassed it with a wire and cut the trace on either side of the blob.

Im now headed to work.

#39 10 months ago

DEC

GRUMPY

Pinside member

OP
Quoted from Definitive:
That relay has Brown with White stripe. ( this is Also the relay that pulses non stop in game mode)

Could this be a faded yellow stripe?

OP
Quoted from Definitive:
But im Headed back under the playfield now... during coil test the F2 SS fuse popped, im now showing continuity to ground on 3J3-6 Red wire, White stripe, (sheet shows vio/blu not accurate). Regardless, with connector unplugged this wire in particular shows contact to ground.

F-2 fuse is connected to pins 6,7 and 8 and should all be a red wire. Pins 4 and 5 should be a red/white wire. Was this showing ground while the game was turned on or off? If it was with the game on then disconnect 1J-19 on the CPU board, did the ground go away? If yes then replace the fuse. Does the fuse blow now?

OP
Quoted from Definitive:
I cannot help but think power from the battery tray made its way down the damaged trace to the chips on either side, (U10 pin 19 and U50 pin 11). Both had continuity to the blob when I located it.

The chips U-10 and U-50 both work with voltages from zero to five volts DC. So depending on which terminal of the battery holder making contact you had either 1.6 volts, 3.2 volts or 4.8 volts. None of these voltages would have cause any damage, but they would have caused the enable signal to stop changing from the low to high which will stop the flippers from working.

#40 10 months ago

C_U

Definitive

Pinside member

Ummmm yup, ill go with faded yellow for sure.
I opened the bundle a smidge to find yellow stripe rather than white.

I counted wrong, pin 4 (red/white) shows ground both while on or off.

Removing 1J-19 stops the contact with ground.

Inserted new fuse, did not blow

#41 10 months ago

DEC

GRUMPY

Pinside member

With the game turned on test for DC voltage on 1J-18 pins with the connector left on the board. Post the readings.

OP
Quoted from Definitive:
I counted wrong, pin 4 (red/white) shows ground both while on or off.

I kind of thought you counted from the wrong direction.

#42 10 months ago

C_U

Definitive

Pinside member

Q79 not reading properly, removing and replacing. All other transistors and predrivers in that square meter in spec.

#43 10 months ago

C_U

Definitive

Pinside member

Quoted from GRUMPY:
I kind of thought you counted from the wrong direction

‍:whoops:

#44 10 months ago

C_U

Definitive

Pinside member

1J-18 connected to the board, and 1J-19 unplugged.
Game ON not Attract mode

1J-18

1=NC (top most pin)
2=4.89 orng/blk
3=4.89
4=4.89
5=4.89
6= no reading (white wire common with 7)
7= same as 6
8=4.89
9=4.89 orng/ble

I through colors in to verify i counted properly, even though a "1" appears at pin 1 lol

#45 10 months ago

DEC

GRUMPY

Pinside member

With J-19 still disconnected and the machine turned on measure ohms from each pin of J -19 to ground. Then start a game and retest. Report the results.

#46 10 months ago

C_U

Definitive

Pinside member

Game on in attract:

J-19 pins to ground ohm test

Pin 1 OL
Pin 2 OL
Pin 3 OL
Pin 4 key/NC/OL
Pin 5 OL
Pin 6 OL
Pin 7 OL
Pin 8 OL
Pin 9 OL
‐‐--------------------------
Game on, and in Game mode

J - 19 to ground ohm test

Pin 1 25.5ohm ish to 72ohm ish fluctuating rapidly
Pin 2 same results as pin 1
Pin 3 OL
Pin 4 OL
Pin 5 key/NC/OL
Pin 6 OL
Pin 7 OL
Pin 8 OL
Pin 9 OL

Performed all tests twice, results remained the same

#47 10 months ago

DEC

GRUMPY

Pinside member

Looks good with the power off you can reconnect any loose connections. Then preform a cool test, note what's not working.

#48 10 months ago

C_U

Definitive

Pinside member

Sweet.

Well looks like

Some coil tests are for lighting as well, ill still list them. I have displays out so i can only read the main and number associated.

#5 a
#5 c
#6
#12 makes clicking noise, not seeing anything change
#14a
#15a
#15c
16

I realize some are insignificant for game play, although I wanted to post everything I noticed to help in the diagnosis.

15833724400138899947908661634442 (resized).jpg

#49 10 months ago

DEC

GRUMPY

Pinside member

#12 should only click in test.
Is your list of the coils/flashers that are not still working?

#50 10 months ago

C_U

Definitive

Pinside member