HELP! Could this be a bad motherboard? stuck at CALL ATTENDANT

[LuckyDog]

Newly acquired PE+ machine (bottom left mpu tray) won't get past  CALL ATTENDANT.

Have used the reset procedure here and other places: https://newlifegames.com/nlg/index.php?topic=3060.msg15274#msg15274

Can't get past CALL ATTENDANT w EEPROM data
Can go thru the statistics menu but that's it

Tried 3 known good MPU boards,
Tried 2 different monitors; all show same symptoms.
Note: everything works in my other cabinet which is a PE+  top MPU tray.

HELP ! !   Don't know what's left to try 

Last Pic is the same board working in my top MPU tray chassis

[knagl]

On the problem machine, is there any indication that the self test button is working? Since you need to press and hold that to start the process of clearing the errors, I'd be looking there first. With the power off, try checking to see if you get continuity on that switch when it's pressed. Also you could trace the wires back to the motherboard to ensure it's plugged in correctly.

[LuckyDog]

Yes, thanks.  Button is functioning.

Heard a ding when holding reset for clearing initial CMOS error.  No dings being heard since.
Call Attendant message goes away momentarily when button released, but come back in about a second.

Motherboards are both 759036-01  Problem machine is Rev F,  Working machine is Rev H.

[LuckyDog]

If  I replace the X24C04 device on motherboard, will I need a set chip or anything to get the new part going?

[LuckyDog]

More symptom description
   
With door open, "Call Attendant with EEPROM Data & Door Open error showing.
Closing door does not update the door open message.  Door open message stays on until the jackpot reset key sends it to the Statistical Data screen.
 
The open/close door detection looks to be working ok; status just isn't updated during whatever error condition is present.

I unplugged the wiring harness from the door buttons, with no change in symptoms.

[knagl]

If  I replace the X24C04 device on motherboard, will I need a set chip or anything to get the new part going?

I don't know specifically what that part is, but I'll say that I've worked on about a dozen PE+ machines over the years and only once ever needed a clear chip. It's incredibly rare to need one for a PE+.

You'll need a SET chip to enable a dollar bill validator if you have one, but that wouldn't be used until after you have the machine up and running.

The open/close door detection looks to be working ok; status just isn't updated during whatever error condition is present.

Are you seeing something different when the door opens that leads you to believe this?

Generally speaking, the "Door Open" message should go away when the door is closed. If the Door Open message doesn't go away, that's an indication that the machine is not detecting the door as closed. You will not get past the error screen without the machine detecting the door as closed.

You might want to consider swapping the door optics with your working machine to verify that the optics are working properly. Be sure to note the different wire colors for the emitter and receiver to ensure you install them in the correct places.

[LuckyDog]

Thanks, I'll take a look at that.

[LuckyDog]

If  I replace the X24C04 device on motherboard, will I need a set chip or anything to get the new part going?

I don't know specifically what that part is, but I'll say that I've worked on about a dozen PE+ machines over the years and only once ever needed a clear chip. It's incredibly rare to need one for a PE+.

Sorry, missed this part.  Th X24C04 is the small eeprom chip on the motherboard that the MPU communicates with.

[LuckyDog]

Update:
Found a clump of crud under the motherboard that appeared to be shorting out some of the signals.
Cleaned it out good & re-assembled.  Took care of the issue!  Now on to the next problem....
Thanks again for the help guys!

[knagl]

That's great news. Thanks for posting the resolution to your issue.