Do a jumper test on the switch matrix of the MPU. Dont have the manual handy, but it should identify the row and column connectors on the board. Pull the two connectors, and using a small jumper wire, jumper pin 1 of the row to each pin of the column, one at a time on the board connector pins. Do this in switch edge test mode. Follow along and see if every row/column combo corresponds correctly to the matrix. Then move to pin 2 and repeat and so on, until you test all 64 combos.

If they show up correctly, then it's a wiring or diode issue in the playfield. If they dont, then board issue.

For unusual behavior like that probably the data buffer IC took a hit. RD board is fine, but yours could be fixed relatively inexpensively, especially if you have the tools to do it yourself. If you want to sell the board as is, let me know, as I have a maverick also with an RD board, but wouldnt mind pitting an original back in.

Page 78 of the ipdb schematics....would be IC 8J or 8H.

You can Pull the corresponding connector for the DT switches at the mpu and enter test to see if they’re still active. If they stop, you can rule out a short on the board, and focus on the playfield.

If it’s the lower left 5 DT bank, double check that none of the wires or switches on that bank are bent/shorting to something.. That area is tight and on the edge of the playfield. Tidy up the wiring as best as you can.

On the maverick project I’m finishing up; That bank was replaced by a previous owner. The original was most likely damaged from the playfield getting dropped inside the cabinet as both of my mdf strips on the inside of the cabinet were busted/gone. I pulled the old staples/nails so nothing was touching the underside of the playfield.

In my case, the drop target bank they replaced the original with was obviously from a different game. Double check the connector from your DT bank to the harness and make sure your wiring matches up to the rest of the main harness/schematic, reconfigure accordingly.

A couple of my switches were out of adjustment and closed as well as wired to whatever game the DT bank came out of. This caused all kinds of crazy switch problems for me.

Mine recently started failing to launch the ball only on Skill shot 2 (start mode). Found if I bang it hard on the lock bar the ball with launch but launches in to the Lauren Belle, rolls down the wire an in play. Kills about 10 sec off the clock. All switch tests are ok.

Then this started: when new ball kicks out to shooter lane the games sounds off as though the ball launched and bypasses the skill shot thinking the ball is in play.

I have manually checked and ran the diagnostic on all switches. Can’t find anything out of sorts under the playfield.

I'd be looking very carefully at the switches.

In particular, the shooter lane switch.

But also the ball trough switches, and the white microswitch that determines if a ball is stacked at the end of the ball trough.

Going into Lauren Belle is usually related to the Paddle Wheel/Left Orbit deflector. This seems to get a lot of vibration because I've resoldered wires to this coil a bunch of times. Of course, anything in the whole orbit that is a ball sense switch should be checked.

The most frequent problem by far with Maverick is broken targets, but after that...

Optos under the Lauren Belle. When these have the slightest problem they miscount the ball, and weird things happen. Solder joints here, but at this point I'm replacing the opto transmitter and receiver with a higher intensity LED.

For optos I've been using these:

https://www.mouser.com/ProductDetail/Lite-On/LTL2F3VEKNT?qs=Sv%252BigzQKaoVYLcEZH8BKGw%3D%3D

For all my Data East / Sega / slightly older Stern pinball opto needs. They are bright. You replace both the transmitter and the receiver with the same part.

Of course, if you are sure your Lauren Belle optos are great, then there is no need to replace them.

The way you describe the problem, it sounds like the game believes that some switch (probably opto) is activated, and thus it thinks the ball is in play instead of where it is.

I'd spend some time in switch test mode and bang on the playfield a bit trying to find where the game is falsely triggering a switch.

Let us know what you find!