Did you switch the power on/off/on with the coin door open?

Is battery voltage making it to the chips when the game is off?

You might find the manual downloadable from IPDB.

If it goes into diagnostic mode every time, but plays ok, I think you have an issue with the battery pack, or the batteries are dead. Take out the batteries and inspect the battery holder for prior damage. Put them back in and check that there is 4.5 V across the whole pack. Check that this voltage is reaching the chips (not somewhere I can get at manuals / circuit diagrams right now, so can't advise there).

I don't think the 2503-1 is an error. The 2503 is informational, something to do with the board set model # (sound type 2, model 503 for Jungle Lord), and I forget what the single digit is for.

Since the diagnostics tests are passing, I'm wondering if maybe one of the coin door buttons (advance) is being seen as pressed as that also enters admin mode.

Side info:

the 1 next to the 2503 is the rom release version and the 4 on the credit is the admin mode it is in, 4 being audit/settings range [0, 50]

I think you have a switch issue - it sounds like the Advance button is being read as closed. I had a similar problem and tracked it down to a broken diode on one of the coin switches. I'd check all of the switches in the same row and column as the test switches.

It's also possible that the chip that implements the switch matrix is bad (I forgot which one this is). You could check that with a logic probe; a DMM isn't much help there.

My guess is your 5101 may be bad.

If you need help with the boards, send em over

I thought it was rom release, but ipdb doesn't show a release 1 available for jungle lord.

IPdb doesn't always have every revision ever made.

Did you replace the battery holder, maybe add a remote holder? If so, can you confirm the battery voltage goes to the chips as previously asked? ( sorry, no schematics to look at right now) I've seen that behavior from a bad throughole at the battery holder on the board and the battery voltage not getting through to the back of the board.

Battery retention voltage will only cause you to come up in diag mode, not cycle through it.

If you disconnected all you do have a logic issue. If memory serves, and this is a big if, your probably looking at a 7404 that is the chip used to decode the coin door switches. But your best bet get the boards to a good repair guy who will fix it, replace all the SCANBE sockets (if it has them) and replace the 40 pin interconnects.

A common problem in system 6 MPUs is the battery damage eats through the top right terminal which provides the ground connection to IC5. When IC5 has no ground connection it will make the game behave like the diag button is constantly being pushed.

Sys 7 is laid out a bit different, but i would still check the diag button signals are making it through properly at IC5.

They are using the IRQ and the diag button on a NOR gate to help take some debounce out of the diag buttons id imagine.

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Thank you, Andrew/Barakandl, for explaining what I was trying to poorly say above. I've had that issue on System 6 boards, because of that exact top right battery holder ground connection. I wasn't sure if it was the same for System 7 but I figured it was worth throwing out there.

That was bad move by WMS using that battery terminal as the spot to connect to ground. I guess they didnt think the batteries would ever leak. =D

I don't think the same battery / through hole issue can come up on system 7, but the same circuit could still be failed on system 7 giving the same effect. Not unreasonable to think an accident would happen at the coin door buttons that sent lamp/solenoid/ whatever voltage up to that circuit and blow it out.

And thanks Bara, 7402, not 7404. I was close from memory with the 74 at least.

Would this apply to a system 3 board as well? I've got the same symptoms as the op. I've re-socketed all the scanbe's and put in a new 5105.

System 6 is the only one with the ground connection at a battery terminal through hole. That said, again the coin door button circuit can be failed.

Just checked the schematic. The coin door buttons are handled a little different on system 3 MPU. IC24, a NAND gate being used as an inverter, is what i would check on system 3.

Check that the coin door advance button signal inverts through IC24... ie put a logic probe on the PIA pins and push the diag button and make sure the signal is alternating high /low

Worth removing the coin door connector on the MPU and see if that changes things. Could have a wire pinched against ground somewhere.

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