Help identifying the 24 V recoil-return pins on the Namco System 10 “EXIO” gun board (Point Blank 3)

[EhmSii]

Hi all,
I have a Lethal Enforcers cabinet that someone previously converted into a Point Blank 2 machine. During that conversion they rewired it for Suzo-Happ .45-cal Type 2 light-guns in the six-pin layout (the usual four signal wires plus orange and yellow for the 24 V recoil circuit).

I’ve now picked up a System 10 Point Blank 3 board set that appears to be set up for four-pin guns. I’d like to make PB3 swappable with PB2, but I’m stuck working out which pins on the PB3 gun board’s J1 edge carry the 24 V return for the solenoids. On PB2 the orange returns land on the gun board’s J3 header; on PB3 I’m reasonably sure the two return lines are on J1, but I haven’t found reliable documentation. Every PB3 manual I’ve found online has been for the system 11 version, so i haven't found any reliable information.

My current approach has been to run jumper leads from the two PB3 4-pin gun headers to the matching conductors in the cabinet’s J3 harness, and most functions are working—except I still haven’t identified the correct 24 V return pins. Any confirmed pin-outs or guidance on locating the 24 V return (and lamp sink) pins on the EXIO gun board’s J1 edge would be hugely appreciated. A pinout would also let me know if I am wiring everything correctly, so any help with that would be amazing.


Current Suzo-Happ Type 2 .45-cal guns in the 6-wire configuration:

Happ lead	Colour	Function
1	Red	+5 V logic
2	White	Trigger (digital)
3	Black	Ground
4	Blue	Opto sensor
5	Orange	24 V return
6	Yellow	+24 V feed

How PB2 handles the coil return​

On the PB2 gun PCB the orange wires run straight to J3-3 (P1) and J3-7 (P2); the board sinks those to ground when it wants to kick the solenoid. (see pics)

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Where I’m stuck on PB3​

The PB3 stack has the a EXIO(G) PCB (8906970602) on top. Its 46-pin “J1” edge goes to a little custom breakout board with two 4-pin gun headers (R W B K only) and three service buttons(coin, p1 start, p2 start). A previous owner hand-jumped the trigger lines from J1 to the JAMMA edge, but the 24 V return pads are not obvious. (see pics)

My Ask

• Which two J1 leads are meant for the solenoid return?
• If someone has a photo or schematic snippet for 8906970602 showing the GOUT driver traces that would be gold.

 

[EhmSii]

A few more details:

• After bringing the PB3 stack home I connected the cabinet’s JAMMA harness to the PB3 main board.
• I then plugged two standalone Suzo-Happ .45-cal Type-2 guns (4-pin versions, not the built-in 6-pin guns) into the two 4-pin headers on the small breakout board.

Power-up results:

1. Game boots normally.
2. Audio plays through both speakers.
3. The cabinet’s start buttons register, but their lamps stay dark.
4. Coin switch registers credits.
5. Pulling either trigger produces the screen-flash and gun SFX, but the solenoids never fire.
6. The TEST switch only keeps the game in the service menu while I hold it—releasing it dumps me back to attract.
7. The guns don’t seem to track or register hits on the screen at all.

I spent some time mapping out how to adapt the cabinet’s built-in six-pin guns, but eventually hit a dead end.