Anyone know...

modessitt

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..why a System 6 (Firepower) would have all the coils fire for a split second when first turned on? It has a memory issue that I'm fixing by replacing the 5101 CMOS, just in case that has anything to do with it....
 
if my memory is correct it's nothing you can do. just some random state of the memory/cpu that the game is in when you switch it on - while the game boots correctly it'll everything set all output lines to low but when you switch it on they can be 'on' and thus one or more coils can activate quickly.
 
If my memory is correct, there is a "blanking" signal that is supposed to keep that from happening. If that signal is not working, then you get all of the solenoids firing at power up and it could possibly blow the solenoid fuse. The blanking signal is part of the power on reset circuit and it continues through the infamous 40 pin connector to the driver board. The blanking signal is an easy trace to break (or cut) when you replace that dreaded 40 pin connector. Make sure that that signal is working on the driver board, you can use an Ohm-meter to verify that the continuity is there.
 
If my memory is correct, there is a "blanking" signal that is supposed to keep that from happening. If that signal is not working, then you get all of the solenoids firing at power up and it could possibly blow the solenoid fuse. The blanking signal is part of the power on reset circuit and it continues through the infamous 40 pin connector to the driver board. The blanking signal is an easy trace to break (or cut) when you replace that dreaded 40 pin connector. Make sure that that signal is working on the driver board, you can use an Ohm-meter to verify that the continuity is there.



Along with the connector, I always make sure all screw holes are filled. Nothing like a floating ground.
 
..why a System 6 (Firepower) would have all the coils fire for a split second when first turned on? It has a memory issue that I'm fixing by replacing the 5101 CMOS, just in case that has anything to do with it....

If you know there is a RAM issue I would resolve that first.

Like others mentioned, the interconnect needs to be replaced if it's original. That will likely solve this problem if the RAM does not. Very common problem with System 3-6 games.
 
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Before I replaced my 40 pin interconnect, I got all sorts of solenoid firing going on during power on. Blew plenty of fuses.

Since replacing the interconnect, I no longer get that spastic activity any more.
 
If my memory is correct, there is a "blanking" signal that is supposed to keep that from happening. If that signal is not working, then you get all of the solenoids firing at power up and it could possibly blow the solenoid fuse. The blanking signal is part of the power on reset circuit and it continues through the infamous 40 pin connector to the driver board. The blanking signal is an easy trace to break (or cut) when you replace that dreaded 40 pin connector. Make sure that that signal is working on the driver board, you can use an Ohm-meter to verify that the continuity is there.

Check the marvin docs and it will detail the blanking signal. It is supposed to do exactly as descrbed above, but there are a couple of chips that can go bad that will also prevent the signal from being set on startup.

ken
 
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