White Water
Williams, 1993My whitewater is having some serious controlled lamp issues.
I have one row that is stuck on and no other lamps working at all. I have performed clay's test method for rows and columns with the same results.
I have tried two power driver boards with the same results. The ribbon cable has been reseated and reversed with no change in outcome.
Tp8 shows that I have 18v.
What should I check next?
Thanks!
My AFM had similar symptoms, and it turned out to be a cracked trace on the power driver board. You've tried swapping that, but it could still be on the CPU board. If you have a logic probe, you could make sure the lamp strobe signals are working.
I'm assuming the Clay test indicated board issues rather than harness, correct?
Here's a pretty good primer on logic probes.
http://www.robotoid.com/appnotes/electronics-using-logic-probe.html
Assuming coils are working, the data bus can be ruled out. The LMP_ROW signal, however is what I would suspect. It's easy to probe at pin 3 or 11 of any of U10 - U13. It should show as pulsing. If it's not, you can work your way backward until you find a location the the signal is pulsing, then you would have an idea of where the break is. All this assumes that the lamp row strobe is the problem.
I replaced my asic chip and game Rom and now have controlled lamps but row 8 is still stuck on. With two different driver boards I get the same results. This is the test procedure that I followed from clay's Testing the Lamp Rows.
If a TIP102 transistor that drives a lamp row is suspected as bad, test it:
Remove the backglass and fold down the display to gain access to the Driver board.
Turn the game on.
After the game boots, press the "Begin Test" button in the front door. Go to the Test menu's "All Lamp Test" test.
Unplug the row connectors at J133 (or J124 on WPC-95) and column connector at J137 (or J121 on WPC-95). These are on the lower right portion of the Driver board.
Connect an alligator test lead to column connector pin 1 of J137 (or J124 on WPC-95). Pin 1 is the right most pin, as facing the board.
Connect the other end of this test lead to one lead of a 555 light socket. One can be temporarily borrowed from a playfield lamp (make sure it's a working lamp first!).
Connect another test lead to the second lead of the 555 light socket.
On the other end of the test lead, clip on a 1N4004 diode, with the non-banded end away from the alligator lead.
Touch the non-banded end of the diode to row connector J133 (or J124 on WPC-95) pin 1. Again, pin 1 is the right most pin, as facing the board.
The lamp should flash.
Move the diode/alligator lead on row connector J133 (or J124 on WPC-95) to the next pin. Again, the lamp should flash.
Repeat the previous step, until the last pin of row connector J133 (or J124 on WPC-95) is reached.
If a lamp row tested doesn't give a flashing test lamp, that row is bad (or the test diode is reversed!). No light or a non-flashing, bright lamp are signs that the respective TIP102 row transistor is bad. Test the transistor as described in Testing Transistors and Coils.
Row 9 ?
There are 8 columns & rows just glancing at the lamp matrix.
J133-9 is row #8 which is transistor Q83 ( Check Q83 if good or bad)
If it tests good work upstream from that.
The only thing that differs between row 8 and all the other rows from the CPU perspective is the D7 signal. If all of your coils are working, that means that the D7 signal is also working correctly, and that basically eliminates the CPU as the source of your row 8 problem.
If you've tried two different power driver boards and both fail the same way, either both are broken the same way or the problem is in the playfield wiring. If you're doing Clay's test correctly, and both boards indicate a problem with row 8, that indicates that both power driver boards are broken in the same way, possibly due to connecting them to playfield wiring with a short and blowing something up.
You can use your logic probe at points G and F in cal50's diagram to narrow the problem down.
Quoted from cal50:I would check all the wiring in row 8 to make sure its not pinched to ground somewhere along everything in that row.
If you are certain its on the CPU board look at :
ULN2803 / U19 & 74LS374 / U18 .
LM339's / U15/U16 .
???
These ICs have nothing to do with the lamp matrix, they're switch matrix and direct switch ICs, and all LM339s.
As herg says, not going to be a CPU issue unless other things aren't working properly either. There wouldn't be just lamp or solenoid issues. There would be issues with every IO devices, switches, GI, solenoids, display, etc. If you're *only* seeing lamp matrix issues, it's NOT the CPU.
--
Rob Anthony
Pinball Classics
http://LockWhenLit.com
Quality Board Work - In Home Service
borygard at gmail dot com
Quoted from Borygard:These ICs have nothing to do with the lamp matrix, they're switch matrix and direct switch ICs, and all LM339s.
I'm guessing he's actually talking about the ones on the power driver board, not the CPU board.
Quoted from Borygard:If you're *only* seeing lamp matrix issues, it's NOT the CPU.
The only exception would be LMP_ROW and LMP_COL, which would mess up ALL of the lamp matrix, not just a single row/column.
Quoted from herg:I'm guessing he's actually talking about the ones on the power driver board, not the CPU board.
He specifically mentions the CPU.
Quoted from herg:The only exception would be LMP_ROW and LMP_COL, which would mess up ALL of the lamp matrix, not just a single row/column.
I am referring to this specific issue, not lamp matrix issues in general.
--
Rob Anthony
Pinball Classics
http://LockWhenLit.com
Quality Board Work - In Home Service
borygard at gmail dot com
Quoted from Borygard:it's NOT the CPU.
..... pinched or grounded wire under PF.......
Quoted from cal50:..... pinched or grounded wire under PF.......
Exactly. Or shorted diode/socket/lug.
--
Rob Anthony
Pinball Classics
http://LockWhenLit.com
Quality Board Work - In Home Service
borygard at gmail dot com
Testing the diodes might be a good place to start. See the "Testing Diodes." section on this page: http://www.pinrepair.com/begin/
As far as the pinched wire is concerned, there is no real easy way to do it I don't think, look for the red-gray wire from row 8 and follow it. Pay special attention where it is connected to sockets and be sure it's not touching anything else.
Shorted diode, socket, or lug should take out a transistor first, shouldn't it? That's the part I don't get. So if I test the associated ULN2803, 74LS374, and LM339's. Which legs should I test with my probe?
Thanks for the help guys. I'll also look into the wiring today.
If a diode is shorted, then it is completing the ground path, bypassing the TIP102's job. That wouldn't kill the transistor, unless I'm mistaken here. You should be able to find the short by taking your meter and putting one probe on the ground and test all of the diodes on the sockets in that row. Is that correct guys? I don't have the schematics in front of me to verify, but I imagine I could take an alligator clip and connect one side to ground and the other to the lamp socket where it gets the ground signal from the TIP102, and the entire row would light up.
Quoted from Hougie:Shorted diode, socket, or lug should take out a transistor first, shouldn't it? That's the part I don't get. So if I test the associated ULN2803, 74LS374, and LM339's. Which legs should I test with my probe?
Thanks for the help guys. I'll also look into the wiring today.
It depends on what is shorted to what. There's a lot of possibilities. In the case of a row transistor, a short to ground wouldn't blow up anything, but a short to coil 50V would.
U10-8 would be the most telling. If that's transitioning, but row 8 is locked on, it's almost certainly a dead TIP102 or a playfield wiring short.
Quoted from thedefog:If a diode is shorted, then it is completing the ground path, bypassing the TIP102's job. That wouldn't kill the transistor, unless I'm mistaken here.
If the cathode is shorted to ground, this is true. Other cases, it depends.
Quoted from thedefog:You should be able to find the short by taking your meter and putting one probe on the ground and test all of the diodes on the sockets in that row.
Not really. Since the cathodes are all connected together, if one in a row is shorted to ground, they all are. You would have to visually inspect them to see if you can find anything. You could disconnect the harness connector from the power driver board, then test for any of the row 8 diode cathodes for continuity to ground to see if there is a short, but it won't tell you where that short is physically located.
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