The top left lane, bottom left outside lane, top right lane that opens the gate and the right bottom inside lane 30,000 point lights never go out they are always on

top left =lamp 18
top right=lamp 18
bottom left=lamp 16
right return =lamp 16

yes

lamp 17 and 19 are on always too, looking at the schematic lamps 16,18,17 & 19 are all controlled by the same 74175 chip (z5)

is there a substitute for the 74175 chip

Tested the 74175 all legs tested around 0.6 but leg 1and 9 tested 0.3

tested the other 74175 and all of the 1 and 9 legs read around the 0.3 so maybe the (z5) chip is ok, is there a replacement transistor for the mps-u45 I could use

I have found the cen-u45 at marco specialties

I tested Q17-20 and they have tested like all the other transistors, looked on the schematics for the coin counter transistors sorry cant find them a heads up would be good

yep have a logic probe, thanks Chris for your help there is a lot of good info you are putting up here

I can rule the 74175 out that chip is good ,and the interconnect harness is good tested it with the dmm , what on the mpu board would I be looking for that controls this lamps

I put a new 74175 in (z5) lamps are still on so that rules z5 out

Tested z4 and z5 pin 9 both the same
then tested z34 with the logic prob and pin 2 was pulsing on 1
and the opposite side there was no pulsing

I am in the learning stage of using a logic probe , anyway probe is set on ttl and pulse
1/ Tested z4-pin 9 only the number 1 light is on the probe, no pulse
2/ Tested z5-pin 9 only the number 1 light is on the probe ,no pulse
3/ " " Z34 PIN 1 IS PULSING ON 0
4/ " " z34 pin 2 is pulsing on 1
I hope you can understand what I am trying to say ,so is the 0 on the probe =low and 1 =high pulse

ok sorry wrong readings on z4 pin 9 it is pulsing on number 1 but on z5 pin 9 there are no lights on at all

Checked z34 again pin 1 is pulsing on 0
and pin 2 is pulsing on 1 , and the lower pin number starts at the top left corner and the highest pin number finishes on the top right corner

Thanks chris you were spot on it was the harness connector the 7th wire from the right (z5) pin 9 is now pulsing all good

Thanks again for all of your help chris, and for more complex problems I am looking forward to it

I Am looking to buy two of this connector-edge double 48 pin to make a harness for the A1-J4 TO A3-J1
http://www.marcospecialties.com/pinball-parts/09-50-5245 I FOUND THEM AT THIS LINK BUT THERE ALL SOLD OUT IF ANYONE CAN
HELP OUT WHERE TO BUY THEM FROM WOULD BE APPRECIATED .