Hi. dont have that pin, but would suspect...
chk if the coin slot you are trying to setup does indeed offer multiple credits for one coin.
chk the credit unit for signs of modifications.' like set to free play".
when the credit unit is on "0", you will not be able to start a game

In the schematic it shows different paths for 1st, 2nd and 3rd coin chute. Which coin chute are you using?

For the 1st coin chute, it is marked on the schematic: "TIE WHEN 2 COIN UNIT NOT USED". You need to look for that white/blue wire and see if it is tied.

There are also three jacks for coin chute adjustment, one for each chute. Make sure you are adjusting the one corresponding to the chute you are using.

Hi pinbrick
how many Coin-Chutes do You have ? (The manufacturer sold the pins with 1 or 2 or 3 Chutes)
I looked up at http://www.ipdb.org/machine.cgi?id=889 - the schematics looks somewhat strange --- and the manual at page-3 shows the different Jones-Plugs for adjustment. AND on page-4 the (strange to me) informations to "2., 2a., 3., 3a." --- example: At end of "2." they mention "When 2nd Coin Chute Adj. Plug is set for 1 Coin for 2 Plays: BROWN-WHITE must also be inserted in pos-2, hmm.

WRITE DOWN how YOUR Adj.-Plugs are set --- then try out all kind of combinations.
The easiest thing would be: Set the pin to "FREE PLAY" so You ALSO can start a game by pressing the Replay-Button --- also start with "Replay-Counter is at Zero". Write, if You want to do that.

Starting a new game by pressing the Replay-Button does NOT decrement the Replay-Counter / Credit-Wheel:
My JPG (from ipdb-schematics) shows "marked green": I believe ALL THIS WORKS -
"red lines and the RESET-Coil on Credit-Unit": Are in question.
We might have to use a Jumper-Wire to make DIRECT connection to transformer-lugs - for now: Check the wires on Reset-Coil (wires soldered-on ?) and check the Credit-Relay (does it PULL-IN ?) and (if it does pull-in at start of a new game): The Switches on Coin-Relay (contact points clean, wires soldered-on ? - a switch that wants to close when the relay starts pulling - does this switch TRUELY closes ?). Greetings Rolf

P.S.: The last page in the manual shows some "wiring on coin-Chutes".

zFlip-Flop-Work-3 (resized).jpg