Fixing a locked on coil on a Gorgar for someone. Was left bumper. It had locked on and trapped the ball in the skirt and they switched the machine off when they saw smoke coming out from under the playfield. Pop bumper is a special, non CPU controlled, solenoid.
Done this, in this order:
Checked coil resistance - All good and plunger moves freely in sleeve so looks like no permanent damage done there
Checked coil trigger switch - not trapped closed
Replaced coil trigger switch diode - Coil still locking on
Replaced coil trigger switch capacitor - Coil still locking
Removed driver board
Tested coil transistor and pre-driver - Both tested good in board but swapped them out anyways just in case
Tested 7402N TTL for the locked coil - Tested good but swapped out (because it was socketed
) anyways just in case
Re-installed driver board
Now, none of the coils are working
.
Solenoid fuse tests good.
Game boots as it should and goes in to attract mode and pressing start starts a game but obviously ball does not come in to play as ball eject coil not working.
None of the coils working in game or in diagnostics. Flippers not working also.
It was getting late and I had to come away so I have not tested for coil voltage on Power Supply board or for power at any of the coils so that will be first thing I do when I go back but in the meantime, anyone have any ideas as to other stuff to check please?
I've never worked on a System 6 game before (well I sorted a battery issue and replaced the capacitor on one of the slingshot coil trigger switches on this machine a couple of months back) but repair guides suggest interconnect can cause issues but doesn't identify any specific, coil related issues (such as none of the coils working at all!) that might be due to interconnect.
Thanks
Andy
Done this, in this order:
Checked coil resistance - All good and plunger moves freely in sleeve so looks like no permanent damage done there
Checked coil trigger switch - not trapped closed
Replaced coil trigger switch diode - Coil still locking on
Replaced coil trigger switch capacitor - Coil still locking
Removed driver board
Tested coil transistor and pre-driver - Both tested good in board but swapped them out anyways just in case
Tested 7402N TTL for the locked coil - Tested good but swapped out (because it was socketed
) anyways just in caseRe-installed driver board
Now, none of the coils are working
.Solenoid fuse tests good.
Game boots as it should and goes in to attract mode and pressing start starts a game but obviously ball does not come in to play as ball eject coil not working.
None of the coils working in game or in diagnostics. Flippers not working also.
It was getting late and I had to come away so I have not tested for coil voltage on Power Supply board or for power at any of the coils so that will be first thing I do when I go back but in the meantime, anyone have any ideas as to other stuff to check please?
I've never worked on a System 6 game before (well I sorted a battery issue and replaced the capacitor on one of the slingshot coil trigger switches on this machine a couple of months back) but repair guides suggest interconnect can cause issues but doesn't identify any specific, coil related issues (such as none of the coils working at all!) that might be due to interconnect.
Thanks
Andy
