Insert Coin Light Flashing S Plus

[vptech2]

Need your help please. I’m working on an IGT S Plus slot machine. I replaced the motherboard and changed the dead cmos battery on the mpu so I had to do a clear and used chip to enable BV. Problem is INSERT COIN light flashes constantly and will not accept tokens. With the door open, I can push button on coin sensor board and ring up 3 credits and the wheels spin.  Machine seems to work fine just won’t accept tokens to get credits. I even tried a comparator from a working machine but no change. BTW I’m using new tokens from a working machine including a new token installed in comparator with sensitivity adjustment turned down to minimum.

[shortrackskater]

Topic moved to IGT S plus section.

Did you replace the motherboard or the MPU board?
Also please read the LOOK HERE FIRST area. It provides a great deal of help for this machine. 

[vptech2]

I apologize for not putting this in the correct forum section. When I acquired the machine, I was told it was working fine but the motherboard had been removed and machine put in storage. The MPU was still in machine. Does turning the jackpot key puts machine in diagnostic mode so I can test coin comparator operation? If so, where can I find a list of these diagnostic options and what each does? I have a list of errors codes but machine does not have any errors.

[knagl]

A flashing "Insert Coin" lamp doesn't necessarily indicate an error. Newer SP chips flash that lamp after the door has been closed, until one paid game has been completed, which was an indication to the casino that the door had recently been open.

[Stayouttadabunker]

Does turning the jackpot key puts machine in diagnostic mode so I can test coin comparator operation?

Turning the Jackpot reset key momentarily, gets you into the internal accounting system of the machine.

...where can I find a list of these diagnostic options and what each does?

With the door open, press the little white test button to get into diagnostics.

The test button can be found in three possible locations on an S+...>>>

1). On the front of the MPU tray when the MPU is located on the left wall of an older cabinet & the power switch is on the floor next to the hopper mount.
2). On the front of the power switch box when the MPU is located on the back wall of a cabinet & the power switch is up above the reel shelf under the topbox.
3). Or on the back of this particular power switch box.

Here's two links to a couple of topics on diagnostic flip cards and how to use them...>>>

http://newlifegames.com/nlg/index.php?topic=18866.0

http://newlifegames.com/nlg/index.php?topic=586.0

[vptech2]

PROBLEM SOLVED! I want thank everyone that chimed in and gave me some suggestions in diagnosing my machine issue. And a huge thank you to Jim with Midwest Slots. I had purchased a motherboard from him and he made a follow up call to see if I got machine operational. After describing coin light issue and sending him a pic of coin comparator, Jim spotted that the machine had the wrong coin comparator. With a few quick modifications, the machine works perfect. 

[knagl]

Congrats on getting your machine up and running, and thank you for returning to the thread to post what the fix was for your machine.