Max Brake display failure fix

[K5IP]

I have a Max Brake and the display became very dim.
So, unable to find any available Max Brake folks (for schematics) I decided to make it operable.
First, I bought a new display unit which I found on the internet. This did not help. The problem not in the display itself, but was in the main circuit board, and since I had no schematic, I could not troubleshoot it.
So, a work around was needed. This involved cutting two pins from a connector supplying the interface connector on the display board, and providing a separate power source, through a switch and power resistor, to the display.
It works well but does not have the automatic power down feature of the original configuration.
If this seems to be a problem (and for several folks who have contacted me, it seem to be),
PM me and I will provide details.
K5IP

 

[GCroyle]

I'd like to see the fix and file it with my records.

Thanks

 

[SnoKing]

Dutch and Di, have a component replacement fix for that! A diode or something goes bad. Let me search for the thread. SNOKING

 

[K5IP]

GCroyle,
I am in Hawaii for a month so only have memory to work from, but here goes.
The power for the back light on the display comes from the main board through pins 15 and 16 of the 16 pin connector on the display board.
I clipped these pins and provided a separate power source to the backlight of the display. I accessed 12vdc at the connecter where it comes into the max brake, fed it through a 50 ohm, 1W resistor, through a toggle switch and wired it to the display board at a separate display input connection. this input A,( for anode, positive), is available through separate terminals marked A and K at one edge of the display board. This sets the display current to about 200MA, about the middle of it's operating range. I do not remember grounding the K terminal, but I must have done so unless it was already tied to a common ground within the display board.
The display is made by crystalfontz and a datasheets showing these connections can be downloaded from the internet.
K5P

 

[GCroyle]

K5P,

That's the excuse, Hawaii. Guess it'll have to do.

I really like my Maxbrake and push come to shove I'll have to get my soldering iron and heat sink out and dive in.

Enjoy your trip.

Thanks

Gary

 

[Dutch & Di]

This is the only info I have on the "dim" light issue. I have to be honest and say I never had to use it so I don't have a lot to go on. Someone passed the link on to me and unfortunately it is all I know about it. https://www.crystalfontz.com/product/cfah2002atmijt-20x2-character-display-module
https://www.crystalfontz.com/product/CFAH2002ATMIJT
I hope it helps. Hugs, Di

Dutch and Di, have a component replacement fix for that! A diode or something goes bad. Let me search for the thread. SNOKING