How do I fix flickering/dim lamps (light bulbs)
Stepper or switch problems
OK, you screwed around with the socket and it didn't help, or you got scientific and hooked up a voltmeter and found that the wires on the socket have no power.Hopefully you used the voltmeter, because that's the easiest way to track down the problem now. All you need to do is trace the circuit back from the lamp and poke you voltmeter probe on each place a connection to something occurs, and you eventually find the switch or the unit that lost the power.
How easy it is to trace the wire depends entirely on how clean the wires are. If they are all grey, your job just got a little harder, but not much because you really need to make sure you are looking at the right wire (the same color wire is usually used a few times in the game in different circuits).
Problem is in a stepper unit
The lamps driven by stepper units are generally things that advance in a sequence like the scores/odds, the extra balls, and the ABC... feature lights.
Big Time Schem |
| score and corners feature lights |
|---|
Let's look at the score lights. As you'd suspect, the score lights are driven directly by the score unit disk. For the sake or discussion, we'll assume the 12 light doesn't work (since that's the position the score disc is drawn in the schematic). The circuit we want to trace is highlighted.
The other circuit through the
spotting disk is what makes the lights flash when you are depositing coins/credits
before shooting the first ball (notice how the extra ball trip relay #2 is in
the flash circuit. We don't want the scores to flash when playing for extra
balls!).
Of course, this give you another hint. If the light flashes, then the
lamp/socket is ok, so it must be the score disc.
The 12 lamp is connected to solid green wire on one side (40) and goes through a couple things to get to a solid yellow wire (30). I you want to just check the lamp/socket, take your trusty jumper wire and connect the blue-red wire (23-1) on the lamp socket to the nearest place you can find wire 30. Note that just because a wire is solid yellow, it may not be wire 30 (it may be 30-1, which is another solid yellow wire used for something else).
Oh yeah, we are assuming you can't tell what the wire colors are, so notice how wire 40 goes to all the lamp sockets? It should be easy to figure out which of the two wires is doing that, so 23-1 is the other one. If you get it wrong, you'll make a spark and blow a fuse.
Now we need to look in the manual.
Big Time Schem |
| score disc - click for a bigger version |
|---|
We know from the schem we are looking for wire 23-1, and we find it on the unit second from the bottom on the right. If you are using a jumper wire, connect this solder lug to wire 30 and the light should come on.
If you are more cautiously using a voltmeter, make sure the unit is stepped to the right position (the wiper blade marked 30 should be touching the rivet at position 29) and see if you can measure about 6V between wire 40 and the solder lug. If not, it's one of these:
- stepper in wrong position
- rivet head at position 29 not connected to solder lug marked 23-1. wiring on back of card needs to be checked
- rivet head dirty or wiper not making good contact.
Problems in a switch
The other lamps are generally controlled by switches in the trip relay bank. Referring to the left side of schematic image above, you can see the Corners Light is controlled by a switch who's label is cut off, but it said "corners relay". You can also see the part of the circuit coming from the spotting disk which flashes this feature light.
Big Time Schem |
| trip relay bank chart |
|---|
The schematic says it's a switch corners trip relay...which one? Now we flip to the chart in the manual and we find a switch with the right two wire colors and a reasonable definition. It looks like we want switch L1, which is a normally open switch. When the trip relay closes, the switch closes and the light comes on. OK, so how does L1 help?
Big Time Schem |
| trip relay bank diagram |
|---|
The picture a couple pages back in the manual answers that. L1 is on the bottom 4 stacks away from the reset coil. Check the wires connecting to this switch, and check voltages. The trip relay bank is pretty dense, so it is usually easiest to just unscrew the whole stack if you need to look more closely at the switch blades/contacts. Just make sure you put it back in correctly!
To adjust the switch, you sometimes need to remove the stack next to the one you want to adjust so you can get a tool in there. Fortunately, the trip switches move a large distance, so it is pretty uncommon to need to bend a switch blade. It's much more common that the wire broke off due to rubbing against the cabinet side when the back door is opened/closed.
