Are there any lamps near the flippers that might have gotten bent and ate touching?

Could be a partly failing rectifier Br.1 on the powerdriverboard.

What is the logic behind this? How does a failing BR1 trigger flippers?

Hmm, I seem to have a related issue, maybe the experts could chime in.

on my World Cup Soccer 94 everything works fine, but both flippers flip once when I do the "Lamp + Flash" Test - anyone come across this before?

thanks!

So, a little more background (yes, I am a SS newbie, be gentle)

Measured 12v at TP3 and it fluctuates wildly between around 8v and 10.5V

Given this 12v I believe is derived from the 18v circuit I tested TP8 and it also fluctuates wildly between around 12.5v and 14.5

In between the transformer (via J101) and 18v I think is BR1 and two Caps.

I searched pinside and found this test of BR1 from zaza
0442be088c9961a219faafad7b4d73489889d49d (resized).jpg
My readings are:

1 - .437
2 - .874
3 - .447
4 - .446

Does reading 2 indicate a failed bridge that would cause the above symptoms or have I jumped to conclusions far too quickly?

thanks, all!

That is correct.
The segment between (+) and (~) is missing or bad
Because of that, the voltage goes up and down when lamps are driven and switches could random trigger.
br1 +.jpg

Many thanks zaza

Replaced BR1

Reading at TP3 is better; fluctuates between approx 11.2 and 12, averages around 11.5

TP8is higher at 14.5 to 15

Game "appears" to playing ok - do I need to worry / do anything more?

TP8 is still low. 17-18 Volt is normal. TP3 must be solid 12.0 Volt

Is voltage at J101 (4+5) and J101 (6+7) 13 Vac ?
Transformer correct jumpered ?

zaza it measure 7v at both 4+5 and 6+7 (and 3.5v at 1+2) ???

Saying that, the machine plays well - as far as I can tell!

Any idea what is going on?

Measure Vac on J101 like this:

13point3.jpg

Oh. Ok then I get 13.5v

(It's been said before but zaza your pictures are brilliant!)

13.5 Vac is perfect.

Be sure the bridge rectifier is soldered on both sides of the circuit board.

Or possible old capacitors (C6+C7) but it is tricky to replace them. When not sure, ask a pro.