Picked up a Firepower, but have a general fuse question

OK..this is what's happening. I've completely rebuilt the power supply board including all caps, diodes, pin headers, the entire hv section, the two big diodes and the filtercap..so everything with the exception of the bottlecap on the big heat sink. I've also replaced the the female connector at J6 with a crimp style.

On both the mpu and driver board, I've replaced both female and male interconnects and all other pin headers. On the mpu, I've replaced the female connector that supplies the +5vdc and +12vdc with a crimp style connector and I've replaced all IC sockets with machine pin sockets.

PSB voltages:
12volt pin on J6 is 13.428
5volt pins on J6 are 5.073
+90volt pin on J5 is 89.47
-90volt pin on J5 is -93.35
+5 on J5 is at 5.073v
Lamps (+16 to 20volts) on J4 is 20.27
Sols (+28 to 38volts) on J3 is 39.42

MPU voltages:
TP1(+12v) is 11.46v
TP2(+5v) is 3.91v
TP3(+5v) is 3.95v
TP4(+5v) is 4.45v
TP7(+4.3v) is 4.78v (w/ power)
TP7(+3.9v) is 4.49v (w/o power)
TP8(+5v) is 4.84v
TP9(+5v) is 4.94v

D17, non banded side
w/power = 4.87v
w/o power = 4.87v
D17, banded side
w/power = 4.78v
w/o power = 4.51v

IC19 pin 22 (using pin 8 as ground) = 4.78v
IC1 pin 8 (without power) has no voltage.

I'm guessing my random resets are due to the lower +5vdc on the mpu. Is there a component that should be looked at that might cause the voltage for the +5 to drop at various points on the mpu?

thanks

-tom

UPDATE: The harness delivers 4.97v and 11.79v to the MPU at the connector... the values change a bit on the ps board when its under load, I'm assuming that's normal (please chime in if that's incorrect)... That being said, TP2 and TP3 are close to 3.9+v. Component on the board somewhere? I have another system 6 board that I'm working on resurrecting to see if I get different values. If anyone has any ideas, they are greatly appreciated.
 
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Had no luck resurrecting the other system 6 mpu. I have a 3rd I'll try tonight if I have the time. I've been looking at the mpu schematic from firepowerpinball.com but cant seem to follow the flow of power and what component might be causing the loss of voltage. Any ideas on what to look at to get voltage proper to TP2 would be greatly appreciated. I'm having a blast playing the game, but it's a bummer when it starts resetting...I then need to leave it unplugged for a time before playing it again :(

thanks

-tom
 
Pretty much ALL of my system6/7 boards have around 3.9v for a number of the test points, with no functional difference. Every component had a small amount of resistance and capacitance to it, which adds up over time. I've gone down that route too, thinking that the low voltage was causing issues, but it never really did.

On my own firepower, I had the same issue with it starting to have odd faults and finally going dead at about the 20 minute mark every day. Turned out to be cracked solder joints in the CPU side of the interboard connector.

Have you tried the freeze spray yet?

-Hans
 
HHaase said:
Pretty much ALL of my system6/7 boards have around 3.9v for a number of the test points, with no functional difference. Every component had a small amount of resistance and capacitance to it, which adds up over time. I've gone down that route too, thinking that the low voltage was causing issues, but it never really did.

On my own firepower, I had the same issue with it starting to have odd faults and finally going dead at about the 20 minute mark every day. Turned out to be cracked solder joints in the CPU side of the interboard connector.

Have you tried the freeze spray yet?

-Hans
Click to expand...

Hans, thanks for the reply and the info on voltages. I have not tried freeze spray yet..mainly because I was wondering exactly what that does? :) but thinking about it, I'm guessing it must cool down the solder. That being said ..I did replace the interconnect...both male (mpu side) and female (driver board side) as well as pretty much every other connector, maybe I need more solder at the joints (although I'm fairly liberal when applying to make sure it covers the pad). On the other hand, what I havent done yet is trace down why my right bumper is stuck on. Now that I know the voltages are probably ok and not causing a problem, maybe I should take a peek at that.

I did read up on coils and saw some reference to each coil having a cap and resistor iirc.. but I didn't see any on my coils (diode only). Think I'll start there as that's a known issue (not that I know what it is..but there is definitely an issue there)..get that fixed and see what happens. I do have another driver board (not sure its status), maybe I'll try that too.

thanks again,

-tom
 
Bullwinkle said:
Hans, thanks for the reply and the info on voltages. I have not tried freeze spray yet..mainly because I was wondering exactly what that does? :) but thinking about it, I'm guessing it must cool down the solder. That being said ..I did replace the interconnect...both male (mpu side) and female (driver board side) as well as pretty much every other connector, maybe I need more solder at the joints (although I'm fairly liberal when applying to make sure it covers the pad). On the other hand, what I havent done yet is trace down why my right bumper is stuck on. Now that I know the voltages are probably ok and not causing a problem, maybe I should take a peek at that.

I did read up on coils and saw some reference to each coil having a cap and resistor iirc.. but I didn't see any on my coils (diode only). Think I'll start there as that's a known issue (not that I know what it is..but there is definitely an issue there)..get that fixed and see what happens. I do have another driver board (not sure its status), maybe I'll try that too.

thanks again,

-tom
Click to expand...

Not much too the wiring for the bumpers, first thing to check is the switches and see if one of them is stuck closed. Do you mean the pop bumpers? or the slingshot/kickers down by the flippers?

Normally a problem like you're having with the resets is due to a failed connection somewhere on the board. It's just BARELY enough to function when starting up cold, but as the heat rises inside the backbox either the resistance goes up or something expands enough to break contact. When you leave it off for a while, it all cools back down to where it makes good contact again. Could be a failing chip, a bad socket, a bad connector, etc.... I'd start on the bottom left near the ROM's.

So what the freeze spray does is to allow you to localize what areas you're cooling down on the board....and without a long wait. Spray a suspected spot, and see if the game starts running well again. It's a trial and error method really, and takes a while to narrow down exactly what spots need to be cooled down to make it function again. But once you have a spot that consistently makes the game run again, then you know where to start looking at solder joints and such.

-Hans
 
HHaase said:
Not much too the wiring for the bumpers, first thing to check is the switches and see if one of them is stuck closed. Do you mean the pop bumpers? or the slingshot/kickers down by the flippers?

Normally a problem like you're having with the resets is due to a failed connection somewhere on the board. It's just BARELY enough to function when starting up cold, but as the heat rises inside the backbox either the resistance goes up or something expands enough to break contact. When you leave it off for a while, it all cools back down to where it makes good contact again. Could be a failing chip, a bad socket, a bad connector, etc.... I'd start on the bottom left near the ROM's.

So what the freeze spray does is to allow you to localize what areas you're cooling down on the board....and without a long wait. Spray a suspected spot, and see if the game starts running well again. It's a trial and error method really, and takes a while to narrow down exactly what spots need to be cooled down to make it function again. But once you have a spot that consistently makes the game run again, then you know where to start looking at solder joints and such.

-Hans
Click to expand...

The coil in question is the right slingshot. Also, i've replaced all the sockets with new machine sockets. burned new eproms for the flipper roms and did the combo rom at IC14 (at least that eliminates 3 sockets as being the culprit)... it's running exactly as it did prior. I'll try to take a closer look at the interconnect and the sockets..make sure all pads are completely covered with solder.
 
Bullwinkle said:
The coil in question is the right slingshot. Also, i've replaced all the sockets with new machine sockets. burned new eproms for the flipper roms and did the combo rom at IC14 (at least that eliminates 3 sockets as being the culprit)... it's running exactly as it did prior. I'll try to take a closer look at the interconnect and the sockets..make sure all pads are completely covered with solder.
Click to expand...

Got a LEON test ROM? Might be worth swapping it in and running a RAM/ROM test of it after the board has started failing.
 
I messed with LEON's test eprom on a spare board I have and it came back as passing all tests with one exception (one or more prom sockets will need to be changed)..but that was to be expected as they are the notorious Scanbe variety. I also tested a 2nd board that came back with many issues, but was definitely cool to run through the steps to find the issues (plus I finally got to mess with my logic probe)

That being said, I was driving to work this morning and had an epiphany (it happens occasionally). I have a 100% working Williams Flash (late production with system 6 boards). Time to swap boards and see if the problem migrates to the Flash machine. That'll definitely tell me if it's board related or something else in the machine (connectors / wires / etc...)

Will do this tonight. I'm guessing it is a board issue but figure this will eliminate everything else (still haven't picked up a can of compressed air for the freeze tests yet, Hans. If this goes as expected, I'll grab some for this weekend)
 
Those intermittent problems are just so damned frustrating, I feel your pain for sure.

Just make sure to check the jumpers, if you're still running a 6-chip firepower ROM set it has that one jumper that needs to be redone.

-Hans
 
HHaase said:
Those intermittent problems are just so damned frustrating, I feel your pain for sure.

Just make sure to check the jumpers, if you're still running a 6-chip firepower ROM set it has that one jumper that needs to be redone.

-Hans
Click to expand...

Will do... where I've already modified the current mpu to do the 3 ROM set, I'll have to reverse it to put it in Flash for that test (no biggie..only did the Zig method and can bleed solder across the pads). Will use the original ROMS to do the test on the flash board and I'll make sure to place the jumper on J4. As much of a pita as this has been, it's still a lot more fun than troubleshooting a video game :D
 
Confused about coils...

OK..I have a coil stuck (lower right slingshot). pinrepair guide mentions it's a special solenoid. It says to test different components for failure, to 1. cut the leg of the resistor and 2. cut the leg of the 22uf 100v cap as they may have shorted. I've done this and still get a locked coil. I should mention that I've disconnected the wire from the non-power lug of the coil so I can just touch it to the coil to test vs. having it stuck on. So then the guide keeps mentioning that it could be a stuck activation switch. I assume the switch it's talking about is the one with the resistor & cap. so, I disconnected one of the wires from that and it's still stuck on. Am I looking at a transistor on the driver board now? ..and if so, not sure which one corresponds to the right slingshot.

any other tests I should run before diving into the driver board? The coil itself shows no signs of melting or discoloration.

thanks,

Tom

EDIT: OK, I see where it's special solenoid 5 (tip 122, 2N4401, and 560,68 & 2.7k ohm resistors). I'll replace all of those and see if that fixes the coil.
 
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Update

Stuck coil was indeed either a failed TIP 120 or 2N4401 (replaced em both as instructed in pinrepair's guide so I'm not sure which was the culprit..but they were probably both toast.. and yes..I replaced the TIP 120 with a TIP 102 :) )

Now I'm down to the random reset. I swapped power boards with my Flash today and about 20 games in, while in the middle of the game, the displays went out and flippers along with the rest of the game stopped working..., quickly shut it off, turned it on and it came right back up and was able to play another couple of games and then shut it off.

At this point I need to recheck solder points on my MPU. I havent had any luck with the "freeze technique" Hans mentioned because each time I restart the game, it comes back up no problem. This is turning out to be quite the ghost!

I do have a couple other MPU boards that I'm working on getting running and might be able to use in place of the existing one, but I'd really like to figure this bugger out! Of course I can always switch out my Flash MPU and watch the problem migrate...

anyway..that's where I am. Any suggestions at this point are always welcome.

On an upnote, I did a completely clean & wax of the playfield and damn it's fast... especially with the right slingshot now working. Cant wait for trouble free days ahead... Unfortunately now it shows me how weak my flippers on Flash are...time for a rebuild on that machine I guess :)


-tom
 
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Yeah, a clean firepower is fast as hell, isn't it?

I don't recall, but did you replace the main filter cap on the power supply yet? I know you did the HV caps, but not sure if you did the rest or not.

-Hans
 
Progress Update:

OK, problem is on the MPU. I put in Leon's test rom and it works all the way through the tests. PIA pins 2-17 working perfectly. I then install flipper rom 1, lights are flashing with test rom in...that's good. Put in Firepower combo rom into IC14, lights are still flashing..still good. remove test rom, put in flipper rom 2, apply power and the lights flash once then lock on. Is it possible that flipper rom 2 is bad?...I suppose so, however I just burned it and check the checksums of the device against the buffer and they matched.

I will burn another one just to test it. Yes the socket is good or the test rom wouldnt have worked, and the 3 sockets being used and the cpu socket are all new machine sockets.

So, I had another somewhat beatup mpu board. replaced all the connector and sockets as well as a crushed test switch and a dead crystal, and that one passed all tests. Placed it in my Firepower and so far so good. It's been on for a while with no lockups..will leave it running for several more hours just to make sure.

So, other than a bad eprom, any suggestions for the now "spare" board?

thanks,

-tom
 
Bullwinkle said:
OK, problem is on the MPU. I put in Leon's test rom and it works all the way through the tests. PIA pins 2-17 working perfectly. I then install flipper rom 1, lights are flashing with test rom in...that's good. Put in Firepower combo rom into IC14, lights are still flashing..still good. remove test rom, put in flipper rom 2, apply power and the lights flash once then lock on. Is it possible that flipper rom 2 is bad?...I suppose so, however I just burned it and check the checksums of the device against the buffer and they matched.

I will burn another one just to test it. Yes the socket is good or the test rom wouldnt have worked, and the 3 sockets being used and the cpu socket are all new machine sockets.

So, I had another somewhat beatup mpu board. replaced all the connector and sockets as well as a crushed test switch and a dead crystal, and that one passed all tests. Placed it in my Firepower and so far so good. It's been on for a while with no lockups..will leave it running for several more hours just to make sure.

So, other than a bad eprom, any suggestions for the now "spare" board?

thanks,

-tom
Click to expand...

I have had chips that test and verify ok on the burner but fail checksums in the machine.
Can always put the suspected bad chip back into the burner and do another verification just to make sure.

-Hans
 
HHaase said:
I have had chips that test and verify ok on the burner but fail checksums in the machine.
Can always put the suspected bad chip back into the burner and do another verification just to make sure.

-Hans
Click to expand...

Chip verifies as good. Burned a second, it also verifies but does the same thing. Grabbed the one out of my now working firepower, and the same thing. Going to continue down the troubleshooting guide. Might change the crystal regardless just because I have a few extras and processor is not the issue as I've swapped in a known good processor.

thanks,

-tom
 
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