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Congo Grey Gorrila Issue

RudeDogg1

RudeDogg1

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So Congo has decided to throw up another issue. The grey gorillas right coil has decided to stop working. Now it did this the other week and I cured it by undoing and doing up the connector a few times. Didn’t work this time. So far I’ve checked:

Coil resistance = fine,
Recrimped and replaced the connector housing,
Checked continuity = also fine,
Checked the voltage when in the test menu (with door closed) = a lot lower than the left one. Left is 6.3v and right is 1-2.25,

I’m thinking maybe the TIP102 (Q41) maybe? Or could it be something else?
 
So I grounded the tab and as suspected nothing.

Put a new one in ran the gorilla test and the switch is registering and the animation on screen moves but the coil doesn’t fire. But it does if I ground the tab [emoji53]. Does that mean there is another component dead?
 
Any ideas? I can’t see anything in the manual about which other components power it (I’m also crap at reading schematics)
 
So when you short the TIP102 you get the coil to fire, but the coil is not firing in the game when it should under test etc?

You can test the pre-drive transistor by the following:

Diode setting on you meter - that's the icon below. Game off. Place the red lead of your DMM on the center leg of the transistor. Probe each of the flanking legs with the black lead. .4 to .6 volts is a normal reading.

86381

If that checks out, your 74LS374 might be gone, they can fail I have had this on BSD for the lights. That's pretty much the whole circuit.
 

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The pre drive transistor is Q34 - a MPSD52 - test as above.

Screenshot 2019-06-03 at 16.06.12.png

It's here.

Screenshot 2019-06-03 at 16.07.29.png
 
Well it still only fires if I ground the tab [emoji22]

Also replaced Q13 while I was at it as it was dead (no perimeter flasher). That’s sparking when I ground it but not flashing. Bulb is good so I assume like the gorilla prob that must of taken out another component down the line sighs
 
Both the right gorilla coil still only works if u ground the tab.

The proximity flasher which had a dead TIP102 it sparks when u ground the tab but the flasher don’t flash
 
I’ll find the pin on the chip from the schematic when home - you’ll need to probe that and it’ll show the output, I think it should pulse high/low, if it’s not the chip will need replacing.
 
EDIT - Let me get you images of the right board LOL

OK - you will need your logic probe set to TTL. If it has a normal reading setting, set to normal too.

Place the red plug on Test Point which is 5V - TP101 is 5V pictured here.

Screenshot 2019-06-05 at 22.01.58.png

Black plug goes to the ground braid.

The suspect pin is pin 5 as per the schematic on U6 - U6 will be labelled on the driver board.

Screenshot 2019-06-05 at 21.18.42.png

You read chips as such starting left of the indentation and hen anti clockwise.

86637

So pin 5 is the suspect pin on the output turn the machine on, and start a game, then measure this, I would expect to see a high reading which is pulsing. Q45 - Gorilla Right is controlled by pin 9 - so that is known good. Cross reference the reading from pin 5, to pin 9.

Screenshot 2019-06-05 at 22.03.40.png

To double check, you could fire the coil in test - this should read high only when firing again cross reference. Discrepencies between the two and you will need to replace U6. I would recommend a solder sucker and socketing this.
 
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Go careful with the probe tip that you don't short adjacent legs on the IC chip, steady hand and all that 👍
 
If you get a spark at the tab, but no flash, that energy causing the flash is going somewhere. Maybe to a short. Check the wiring connectors to the flasher and make sure there isn’t some other connector into which it could be plugged.
 
So just probed 5 - 9 (ooer)

5 = HI when running the right gorilla coil test = no change
6 = HI when running the right gorilla coil test = no change
7 = HI when running the right gorilla coil test = HI PULSE
8 = HI when running the right gorilla coil test = HI PULSE
9 = Hi when running the right gorilla coil test = no change
 
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