(Topic ID: 178378)

AFM - Flasher issue

By Dkjimbo

7 years ago



Topic Stats

You

Linked Games

#1 7 years ago

Another (maybe? hopefully? simple problem on an AFM I would love some help with -

The flasher in the playfield set between the 3 pop bumpers does not work at all. The entire game has LED including flashers. Every other flasher in the game works.

The TIP102 transistor associated with this flasher is Q30 (Jets). When I grounded the tab of the TIP102 with a lead on alligator clips, the flasher lit up. So there is no issue with the bulb or the wiring from the bulb to the board.

I replaced the TIP102 and the flasher is still not working. There are no apparent board defects (solder bridges, scratched traces, burned traces, etc)

The game reports no errors and has no credit dot.

What else could cause the flasher to be INOP if the wiring is good all the way, the bulb is good and the TIP102 is good/brand new?

#2 7 years ago
Quoted from Dkjimbo:

Another (maybe? hopefully? simple problem on an AFM I would love some help with -
The flasher in the playfield set between the 3 pop bumpers does not work at all. The entire game has LED including flashers. Every other flasher in the game works.
The TIP102 transistor associated with this flasher is Q30 (Jets). When I grounded the tab of the TIP102 with a lead on alligator clips, the flasher lit up. So there is no issue with the bulb or the wiring from the bulb to the board.
I replaced the TIP102 and the flasher is still not working. There are no apparent board defects (solder bridges, scratched traces, burned traces, etc)
The game reports no errors and has no credit dot.
What else could cause the flasher to be INOP if the wiring is good all the way, the bulb is good and the TIP102 is good/brand new?

Check the predriver Q19 with a DMM, check for incoming signal to base of Q19 with logic probe in test mode. That will determine if you need to work your way back from there to find the problem, or if a problem is between the predriver Q19 and driver Q30.

#3 7 years ago
Quoted from Dkjimbo:

What else could cause the flasher to be INOP

IF everything else is good (resistors, diode next to TIP102, i would check the driver transistor -before TIP102- and of course the output of the IC - I presume it`s a LS374.
You did not mention if you have multimeter, logic probe or ...nothing.

If you have multimeter, it`s always easy to compare voltages-resistances with the other drivers next to it (of course you have to activate those outputs).
Logic probe can show you if LS374 is defective or not.

#4 7 years ago
Quoted from loscanones:

IF everything else is good (resistors, diode next to TIP102, i would check the driver transistor -before TIP102- and of course the output of the IC - I presume it`s a LS374.
You did not mention if you have multimeter, logic probe or ...nothing.
If you have multimeter, it`s always easy to compare voltages-resistances with the other drivers next to it (of course you have to activate those outputs).
Logic probe can show you if LS374 is defective or not.

I have a decent multimeter but no logic probe.

#5 7 years ago
Quoted from Dkjimbo:

I have a decent multimeter but no logic probe.

You can use a multimeter too, just to check for the presence of the pulse. The only thing is that you won't be able to reliably see the amplitude, and it happens pretty quick. I actually use my DMM more than a logic probe for troubleshooting logic circuits.

#6 7 years ago
Quoted from Dkjimbo:

I have a decent multimeter

Put that flasher in test mode and measure the pulse voltage in base of TIP102 and then pulse voltage in base of previous transistor - should be Q29. You must have a clear pulse on multimeter...depends how fast is it, you will see .3 to .7Volts
Note that IF pre-driver transistor is SHORTED will be NO pulse.
IF TIP102 has NO pulse measure integrity of pre-driver - hope that you know how.

#7 7 years ago

Between this and the other thread, it sounds like you REALLY should just have your driver board looked at.

Promoted items from the Pinside Marketplace
From: $ 11.00
From: $ 159.95
Cabinet - Sound/Speakers
PinSound
Sound/Speakers
$ 16.50
Lighting - Led
Lermods
Led
From: $ 17.99
Eproms
Matt's Basement Arcade
Eproms
From: $ 64.95
Cabinet - Sound/Speakers
PinSound
Sound/Speakers
From: $ 399.95
Lighting - Led
Pin Stadium Pinball Mods
Led
$ 9.95
Eproms
Pinballrom
Eproms
From: $ 110.00
Playfield - Other
Arcade Upkeep
Other
$ 44.95
Playfield - Toys/Add-ons
PinBoss Mods
Toys/Add-ons
14,000
Machine - For Sale
Nashville, TN
From: $ 33.00
Gameroom - Decorations
Rocket City Pinball
Decorations
$ 27.99
Lighting - Interactive
Lee's Parts
Interactive
$ 12.00
Tools
Nezzy's Pinball Prints
Tools
$ 95.00
Cabinet - Sound/Speakers
Pinball Mod Co.
Sound/Speakers
$ 399.00
Cabinet - Decals
Mircoplayfields
Decals
$ 285.99
Cabinet - Other
PinSound
Other
$ 30.00
Playfield - Other
YouBentMyWookie
Other
$ 109.95
Electronics
PinSound
Electronics
14,000
Machine - For Sale
Bristow, VA
$ 17.50
Cabinet - Other
Rocket City Pinball
Other
Wanted
Machine - Wanted
Westwood, NJ
$ 5.00
Playfield - Protection
UpKick Pinball
Protection
$ 35.00
Cabinet - Other
Rocket City Pinball
Other
$ 48.00
Lighting - Backbox
Arcade Upkeep
Backbox
$ 37.50
Boards
Pinball Haus
Boards
$ 15.00
Cabinet - Sound/Speakers
Gweem's Mods
Sound/Speakers
From: $ 5.00
Cabinet - Other
Pin Monk
Other
10,250 (OBO)
Machine - For Sale
Onekama, MI
$ 399.95
Lighting - Led
Pin Stadium Pinball Mods
Led
Hey modders!
Your shop name here

Reply

Wanna join the discussion? Please sign in to reply to this topic.

Hey there! Welcome to Pinside!

Donate to Pinside

Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!


This page was printed from https://pinside.com/pinball/forum/topic/afm-flasher-issue and we tried optimising it for printing. Some page elements may have been deliberately hidden.

Scan the QR code on the left to jump to the URL this document was printed from.