I have a T2 that blows F105 on power up and also blows the 8amp fuse at the service plug port. It sounds like a coil/coils lock on with a loud buzzing sound before the fuses blow but I am unable to catch it. I am also unable to see anything on the DMD on boot up. This pin has been hacked a bit but the driver board and DOT matrix controller has been gone through by Chris Hibler recently.

If I pull J107 the game boots up with GI coming on. After research here on Pinside I have checked the ribbon cables and made sure they are installed correctly with the red stripe on pin 1 at each connection.

My plan is to check coils 1-8 per an earlier post I found here on Pinside. Should I disconnect each single wire from coils 1-8 then attach one at a time to find out what coil is blowing F105? Also it looks as though I should test the transistors (64, 66, 68, 70, 76, 78, 80 and 82) to see if any are shorted to ground.

Which move should I make first? Pull the board and test the transistors or disconnect the single wires on the coils and then reattach one at a time?

I also checked TP2 and TP3 test points. TP2 = -4.9V and TP3 = -12.0V not sure if this matters.

Thank you for any direction on this.

Ok I tested the transistors and I have a couple of questions.

I went to pinwiki and followed the directions on testing TIP-36c transistors which states to put the red lead to the center leg and to place the black lead to the flanking legs in turn. When I do this I get no reading on the DMM but when I place the black lead to the center leg and place the red lead to the flanking (outer) leads in turn I get a readings on the DMM. I did test this on the backside of the board.

The readings I took were off of all the TIP-36c transistors and it looks like there are two bad transistors (Q66 & Q82).
Here were the actual readings on each leg on the backside of the board:
Q64 Left leg .51 & Right leg .44
Q66 Left leg .00 & Right leg .12
Q68 Left leg .51 & Right leg .44
Q70 Left leg .51 & Right leg .44
Q76 Left leg .51 & Right leg .44
Q78 Left leg .50 & Right leg .44
Q80 Left leg .51 & Right leg .44
Q82 Left leg .00 & Right leg .00

Reviewing the manual it looks like Q66 is Solenoid 6 (Left Kicker) Violet/Blue wire & Q82 is Solenoid 1 (Ball Popper) Violet/Brown wire.

I plan on replacing Q66 & Q82. Is there anything else I need to test prior to booting the game back up after these two TIP-36c transistors are replaced?

Q66 & Q82 replaced and tested good on the board.

Fingers crossed when I get this installed and hopefully I do not have coils lock on again. Planning on installing this in the next couple of hours.

Well installed the driver board back in and I wish I would have seen your post PinballManiac before booting up but some good news as well.

First the good news, Game did boot up and I heard no coils lock on after replacing Q66, Q85 & Q81. The dmd did turn on but it did have some issues as did the sound, so decent progress. The bad news, I did start to smell burning so turned the game off immediately and raised the playfield to a small amount of smoke, the culprit was at the single drop mechanism. It was not the larger coil AE-26-1200 that raises the drop target, it was actually the smaller coil SM1-26-600 that drops the target back down, picture of burnt coil to follow.
I was able to unplug the single drop mechanism and I did boot the pin back on. At that point most everything seemed normal other than the dmd had lines in it and the sound wasn't what it should be but I was able to check all other coils and game play by tossing the ball around by hand so I am definitely moving in the right direction.

At this point I will probably have to replace the small coil SM1-26-600 because it looks toasted. I guess it would be a good idea to pull the driver board again and figure out which transistor runs the SM1-26-600 coil to see if that was the problem for it to lock on. Back to the manual and pinwiki yet again.

If anyone has any advice or idea's it is greatly appreciated. I am finally diving into the repair side of pins/boards and I have much to learn but am eager to do just that.

Burnt SM1-26-600 coil

0912191943 (resized).jpg

I did try to reseat the ribbon cable earlier and it did not help. Looks like an original cable so I may need to purchase a new ribbon cable.
I have pulled the driver board and plan on replacing Q52 tomorrow at work, it did test bad. I will have to order a new coil and ribbon cable so it will probably be about a week before I get the parts here at the house, once I do I will be back to give an update.

Thank you both for the assistance and direction on this.

OK all, Back up and running once again. Q52 was replaced, coil replaced and a new ribbon cable took care of the sound issue and the lines in the dmd. Game will get a great test next weekend at Pinagogo.

Thank you for the assistance and direction

Game played great at Pinagogo pinball show for three days straight. Thank you all for the direction on the fix.