Quoted from flashinstinct:Ive never tested a driver board before. Any pointers... kinda like A B C. Ive been very lucky with the past games that I have had and never really had to test anything. I popped the target up manually and it locks in place. when it gets hit by the ball the target drops.
Here`s another angle.
Do you have this diode hooked up to your
These two coils do not have diodes.. Per pinwiki for the coil
13 Testing a coil
If a driver transistor shorts on, it will cause the associated solenoid to activate at full power and stay activated. If the coil wire gets hot enough, it will burn out its plastic coating, shorting the wires and dropping the resistance to near 0 Ohms. If this happens and you replace the broken driver transistor, but you don't check the coil, the shorted coil will cause the transistor you just replaced to be damaged.
If you are unsure of the condition of the coils in a machine it is very wise to check each coil's resistance *before* switching the machine on. The human nose can be a very useful tool in diagnosing when something has burned, so use it!
Some flipper coils are "two coils in one," where they have a power coil and a hold coil. These are normally identified as having three lugs instead of two. You can treat these as two "separate" coils for the purposes of the tests below.
13.1 Testing resistance
To test a coil's resistance:
set your DMM to 'Ohms' and attach your red and black probes to the coil lugs.
If you see a reading of less than 2 Ohms, the coil has either shorted internally or there is a wiring fault. Note: Some flipper coils will read less than 2 ohms but still be fine.
Desolder the wires going to the coil lugs and check the resistance across the coil lugs again. If it reads the same value when disconnected, then the problem lies with the melted coil. If the coil resistance reads 'normal' when it is disconnected (ie the coil is 'ok'), you may have a wiring or driver transistor issue.
It is wise to check all wiring and transistors associated with a melted coil before replacing it and powering on again.
Transistor
http://www.pinwiki.com/wiki/index.php?title=General#Testing_a_Transistor.2C_Silicon_Controlled_Rectifier_.28SCR.29_or_Field_Effect_Transistor_.28FET.29