Lights not working when they should?

[robm]

My wife had been playing the Williams Flash game (sys 4) and left it half way through the game - i came 3 or 4 hours later and started a new game (i'm not sure if this has any relevance but i thought i'd give the background).  Now there are a number of lamps (that all work fine in the lamp test) that don't turn on when they should (and were working fine this morning) - these also work when the game is in game over mode.

The player 1 - 4 illumination (on backglass) doesn't work to tell who's turn it it - although it does turn on to illuminate who had the highest score at the end of the game

The Thunder and Lighting lights (on playfield)  don't turn on when the 3 drop targets are all hit, but when they are hit a third time for Tempest - all three come on (as they should) and then Super Flash also works.

The 5000, 1000, Extra ball lights for when the 5 bank of drop targets are hit also don't come on when they should (but the Shoot Again light does after the Extra Ball has been scored.

Don't really know where to start looking...

[Extra Ball]

I would look at fuses first, but others here may just know the problem (I own flash so am interested in this).
:)

[Retropin]

The clue to this i feel is in this line..

Now there are a number of lamps (that all work fine in the lamp test) that don't turn on when they should (and were working fine this morning) - these also work when the game is in game over mode.

If something works fine in test mode but not when its getting played then the CPU is not getting a signal to strobe when it should, so its an input problem.

High scores working but not player, says that all is good - the CPU is sending high scores to displays, but its not getting signal to register player 1 etc - could well be on the switch matrix input - id be checking here first

[robm]

Is this the same switch matrix i had on another thread (http://aussiepinball.com/index.php?topic=341.15) a couple of weeks ago - IC11 the PIA on the driver board?

When i tested the IC17 and IC18, they were the opposite to what you suggested.

Is there a way to test the switch matrix itself or is that done through testing the other chips i have already done?

But it is all very strange that if this is the problem, you would think it would have had the non illumination probelms all along rather than just popping up today...although stranger things have happened!

[robm]

Also, the fact that the Thunder,Lightning,Tempest, Super Flash lights all work but ONLY after the 3rd and 4th stages have been reached (ie: after three rounds of drop targets being completed) makes me think the CPU is getting the signal that the 1st and 2nd parts of the sequence have been completed but is just lazy and doesn't display it until the 3rd part has been completed....

[Retropin]

Could be as basic as a connector... machine is left on for a while, connectors have tarnished over time, heat builds up causing more resistance and tarnish - signal drops out.

The IC17 and 18 were these the non inverting buffer chips on the schematic that turned to to be inverting on the actual game?

Thats OK - was  a misprint, doesnt really matter if they were inverting or not, its the inconsistences of the input/ output thats important...

.. schematics are fine, but its always best to have the game in front of you, anything else is just a guide

[robm]

I'm thinking it may be a connector - just made another discovery, if i drop the bank of three drop targets - the Thunder light should come on - it doesn't...BUT... when i hit another stationary target the Thunder light illuminates!!!

Also there is another switch that when hit, turns on the other lights related to the bank of 5 drop targets!!

I just have to work out what will get the player illumination to work now.

I'm assuming the 1st place to look will be all the connectors at the drop targets and these two other seemingly related stationary targets??

[Retropin]

Simple is best! So start at the connectors - something isnt getting through. you are dropping a signal somewhere - the fact that another switch will trigger the correct light to work would suggest its not PCB related.

When games do odd things after being on for a time is normally heat related. tarnished pins are point #1 to start from

[Strangeways]

Sounds to me like a dip switch setting ?

could it be that simple ?

[robm]

Problem solved!!  As suggested the problem was a connector somewhere.  I ended up pulling all the connectors to and between the MPU and driver board and also the joiner ones between the playfield and the MPU - turned it on and everything worked as it should.  Thanks again for the help.

I also put a very small amount of WD40 on the connectors...unsure if this was a good idea or not.

[Strangeways]

Problem solved!!  As suggested the problem was a connector somewhere.  I ended up pulling all the connectors to and between the MPU and driver board and also the joiner ones between the playfield and the MPU - turned it on and everything worked as it should.  Thanks again for the help.

I also put a very small amount of WD40 on the connectors...unsure if this was a good idea or not.

Rob - Nice one 

BUT - All you have done is Identified the problem and bought some time until it happens again.. You will need to replace those connectors in time.

There's an entire section devoted to the interconnectors here;

http://www.pinrepair.com/sys37/index1.htm#interconnect


Use a pencil eraser to clean the connectors - Never use WD40

[ajlaird]

Use a pencil eraser to clean the connectors - Never use WD40

Would a fine sandpaper (eg emery board) help with this without damaging the connectors?

[Strangeways]

Use a pencil eraser to clean the connectors - Never use WD40

Would a fine sandpaper (eg emery board) help with this without damaging the connectors?

Yes it would work - but on some connectors, you are removing a protective coating on the pins to prevent corrosion. I'm not EXACTLY sure of it's properties, but it is easier to clean with a simple erasor.