Do you have a DVI cable to try for the primary (top) monitor.  I have never tried to use the DP port for primary.

Yeah, it's got a DP->DVI converter on it, I'll try a direct plugin to the DVI port and see what happens.

Varta battery has been removed. Sent you a PM about a board rework Lookes.

Sounds like you are all set. You need to either get that board reworked, or get a reworked 502A or a 504B.
That Varta has to be removed. Looks like damage has already been done.

Hello,
PT-2 slant top purchased back in December 2023 and everything has been working great.
Recently we can only see the message (Data in stock is wrong check RAM or circuit.  Turn on and off reset s/w to clear data in stock). 
No keys provided so I shorted out the two wires going to the reset switch. 
This cleared the Data in stock is wrong check RAM or circuit, however, now we see (Now, power up self-testing wait for a while).  This is cycling every few seconds and I can see Hopper Runaway for a brief second. 
Pulled out the hopper and removed all coins in hopper and the shoot.  Checked knife and nothing is jammed.  Wheel moves freely and coins can go up the shoot.

Possible causes:
Power Supply?
Hopper Motor?
Is there a Fuse in between?

Any advise would be appreciated.  My mom is missing some of her entertainment!!