Hi just acquired a scared stiff. The right flipper was not working.

What I have done

Fuses were blown replaced these.
Tested Voltage on right flipper coil was 21v on all 3 tabs.
Tested tip36 q90 power driver and it was shorted.
Replaced Tip36 q90 and now when I turn the game on the right flipper is in the up (Hold) position. When i turn the power off after a few seconds the flipper lowers.
Suspected q92 Tip102 right flipper hold transistor. Showed shorted on 1 leg so I replaced it.

OK heres as far as I got. Flipper is no longer stuck up.
Voltage on right flipper coil tabs are now all 71 volts.
Right Flipper now works but not powerful like half power.
I detect it may be flipping on the low voltatge setting.
No more fuses being blown.

When in flipper test the power does nothing but the hold raises the flipper as normal.

Just to mention I unsoldered the wires to the right flipper coil and wired up the left flipper wires to it and it worked fine.

Could anyone please help me with this problem.

Thanks in advance.

Kindest regards David

Bump anyone have any ideas?

Hi thanks for the reply. I shall try that tomorrow and report back to you and let you know whats happening.

Regards David

I swapped them around it worked for 20 or so flips now its back to it normal slow flips.

Regards David

Still unsolved. I am thinking now it must be on the driver board.

If I ground out the power Tip 36 nothing happens.

If I ground out the middle wire on coil (yellow wire) it works as normal.

Anyone?

I replaced all flipper opto's with new ones no change.

Checked all the molex you mentioned and reseated them many times no change

Here is a video of what is happening so you can see for yourself looks like a flipper mechanical binding but is not as i rebuilt them and the plunger moves nice and freely. The flipper gap is good too.

Hi I have 74v on all 3 lugs which is about right. There is no mechanical error.

I already done that test from yellow wire to ground middle coil lug. But i see you are verifying no break in the cable.

Ok I have done that test 120.12 to ground and the flipper flips strong same as the left one.

When I do the test 212.12 in attract mode to ground i get the callout as if someone is pressing the flipper.
When I do the test 212.12 in test mode it flips slow.

I have replaced the Tip36c Q90 and Q92 no broken traces that I can see and checked continuity to next soldered point.

Thank you for having the time to help me with this..

Anyone else have some ideas please chip in

Thanks for the ideas guys really boggling me this one.

I obtained these opto switches.

https://www.pinball.co.uk/shop/arabian-nights-pinball-machine-parts/flipper-opto-board-assembly-a-17316/

Willing to try any other tests you guys have. Is it possible the power transisitor q90 has a broken track somewhere?

Regards

Thanks guys all of you for your input. I will do all the tests today and get back to you all later.

Thanks again.

Ok tests so far.

Flipper opto Switches indeed getting the 2.5v half rail on them.

Regarding grounding Q91 the flipper flips normally. I have checked both outside legs with ground on Diode test and they come up ok. around 400 to 600. I will probably change just to make sure.

Regards David

Thanks Homepin for the advice and the kind gesture of sending me some to try. Of course please send me a bill when I have tested them as I don't expect anything for nothing

Hi Leiden Both q90 and q92 are confirmed good. If you are talking about grounding them q90 does nothing and q92 flips the flipper slowly to hold position. Q91 flips the flipper normally.

Regards David

Just changed out the right flipper opto switch and it worked perfect for 38 flips then slow again. tried all combo's of old opto and new ones with left and right flipper still slow.

It seems after a couple of days of not turning the machine on it works again for about 30 flips. So may have worked without changing the right opto switch.

This is the part that worries me but happy to do more tests until these correct opto switches come from Homepin that he kindly sent me .

Not changed out Q91 yet although it shows good on diode test.

Regards David

Hi Leiden thanks for your input.

Test12 flipper test all work except the right power does nothing same as before

Hi today thanks to the very kind gesture of Homepin I received his package not only included the Flipper Opto's but some nice toys. Thank You very Much!

I plugged them in and they lit up as they should do but still the same problem. Before I replaced them I got the usual 30 or so good flips out of the right flipper before doing the same thing again. It seems when something is warmed up on the cpu or driver board it fails.

I think the answer is to send my boards to a friend I have to check out first.

I will then update you with any known problems so it may help someone else in the future.

Homepin I am very grateful for your help. Although it didn't solve this issue please send me a bill for the time and post and cost as I would like to square that up with you by paypal.

Kindest regards David

Hi i have felt the coil after and it is not even warm. The machine has to be off for at least 24 hours before i get the 30 or so good flips out of the right flipper. Thanks for the suggestion though

Hi guys just a follow up and problem is now solved.

I sent my boards off to Bob of Pinball toys to try and detect a fault on the driver board. He put it in another wpc 95 machine and indeed it done the same thing pointing at a problem on the driver board.

After a long investigation it was found D99 one of the diodes on the driver board had failed. It was replaced along with new transistors along with that circuitry in case it had stressed them out. So all working and extremely delighted that I can now play it.

This may help someone else with similar problems.

Thank you everyone for your help and suggestions.

Kindest regards David