Yes a fuse can look good but still be bad.Put the meter setting on continuity and place one lead on one side of the fuse and the other lead on the other side.You should here a beep if no beep means the fuse is bad.

I'm really not sure, but try with ohms if it gives no reading, might be bad fuse. thats how I detected my blown fuse last time.

You cannot determine a fuse by looking at it. Like mentioned above, use a multimeter and set it for continuity. I think thats a basic function on all meters. The audio feature is not on all meters. Mine has the audio feature but you must select it on the meter. Place the meter's leads on each end of fuse. With the audio feature you get a tone, if no audio feature you look at the display to see a reading thats not 0. Get a tone or numbers fuse is good. No tone or a 0 reading=fuse bad.

Many times you can check a fuse while its seated but I had instances where I had to remove the fuse before checking. A bad fuse can check good sometimes if you leave it seated.

No don't try to check the fuses under load! Turn machine off and pull each one out and check them individually.

Power off! Take the fuse out of the holder and test it.Never try to test the fuse while it's in the holder with the power on.

Check the switch in the ball through and check the switch in the drain hole.

You cannot check the fuse for resistance while installed but you can check for voltage. I do that all the time.

Instead of setting the meter the ohms and putting a lead on each side, select volts on the meter. Then put the black lead to ground and the red lead on one side of the fuse and read voltage. after reading one side then move the red lead to the other side of the fuse and read voltage. If the voltage is the same on both sides the fuse is good. If one side has power and the other does not the fuse is bad, simple.

I do this at times because I want to know the voltage so I can learn two things at once.

I don't see any reason that you cannot check for fuse continuity while the fuse is installed. It should still show whether the resistance is zero or infinite with the fuse installed. I always use the ohm setting on my meter. I would not do this with the machine plugged in though, because you do not want to risk shorting out something.

I am and electrical engineer, so if I am wrong then tell me why that is. Thanks

Also, the voltage method between each end of the fuse and ground is a legit way to test fuse contunuity, but the machine probably needs to be on and you have to be careful not to short something as I said before.

hope this gets resolved, please let us know how the fuse problem works out too mojozone, would love to learn.

You can check the fuse for continuity while it is in the holder. However, I've had a lot of fuses that were fatigued - some the end caps fell off of when removing them, some that tested good until they were flexed etc.

I remove them because I like to make sure they are the correct value.

http://www.ehow.com/how_7590933_check-smd-fuses.html

I am guessing that the optical sensor (or mechanical switch) in the ball trough is not seeing the drained ball. The machine probably does not activate the next ball until the last ball is sensed. I am still somewhat new to pinball work so it is my guess based on my limited understanding of how the parts work together.

By the way, very good advice John. Those fuses are pretty cheap and can easily come apart as a physical failure rather than an electrical failure. After I bought my machine NIB I had one fuse failure and decided to buy a 5-pack of every size the machine uses through pinballlife just so I could fix the machine quickly anytime a fuse went out. They are very inexpensive to keep spares on hand.