Scoreboard repair

[kellys_eye]

Sorry output is reading 3.6v on the center pin on the master board.
4.5 volts on the slave boards.
Number generators are getting 4.9 v

Something isn't right. The idea that three as-good-as-identical boards have three different voltages coming out of identical regulators that are supposed to have a FIXED output (usually within a few % of the stated value too) points to a problem with your measuring device!

 

[Milhousesmom]

They are on-board programmed controllers so replacement is going to be 'impossible' unless you can find the boards OEM and get spares.[/QUOTE]


If this is the case I am sorry to have wasted everyone's time. That is disappointing.

BTW. The 1117m3 has two resistors connected to the left pin so I am assuming it is an adjustable regulator like it was suggested in this thread.
The out put on the master board from the regulator was 3.6v. Would that have caused the IC to short since 3.6 v is above the operating range of the mkl25z128vlh4 IC?

Thank you to all who tried to help. This forum is amazing.

 

[kellys_eye]

I'm still mystified as to the differences in volts from those regulators as the boards (master or slave) are, basically identical aren't they? Certainly if the regulators all power those MKL25etc devices they should all have the same supply voltage (give or take).

Are you sure the supply IN to that board is ok? The 12V line is a STEADY 12V and not got massive ripple and/or HF noise on it? Can you apply 12V DC from a different supply source? If the original 12V source supply is SMPS derived and has dodgy output filtering (typical problems with such supplies actually) then it could be 'messing around' with the regulators on those boards. A simple test meter won't show noise and/or fast fluctuations so you'd have to 'scope the supply to be sure - which is why I suggest finding/using another 12V supply and bypassing the OEM source.

You could use an old PC power block to get a 12V supply but you may have other options..... tell me!

 

[Milhousesmom]

Just an update. I've replaced all the mkl25z128vlh4 and all the 1117m3 voltage regulators. All the lights now turn on and I get steady 12 v on each board. Unfortunately none of the functions work. I have verified the continuity of the wires and the buttons are all testing fine.

Am I correct in guessing that it is because they needed to be programmed?

Thanks

 

[kellys_eye]

Am I correct in guessing that it is because they needed to be programmed?

Indeed you are.

If you had the relevant reader/programmer you could try to extract the code but that also assumes the OEM didn't 'lock' the device to prevent just that.

TBH it would be easier to program an Arduino to drive the board instead.

 

[Milhousesmom]

I thought about that but that is beyond my skill level.

Thanks for all the help everyone.