Hello pinball technophiles! I have an issue with the chase lights on my DEST. As soon as I turn on the machine the first set of lights comes on immediately. The other two sets (there are 3 on each side) flash in sequence and speed up/slow down as they're supposed to.The first set is powered through the orange and brown wire. The other 2 are orange/red and orange/black. The leads from the CPU come from CN3 and are blue/red, blue/orange and blue/brown.

I've replaced the chase light PCB with a new one from Marco. The chase light ropes all work. I tested the TIPs on the PCB and I also did a continuity test throughout the whole wire harness that supplies the chase lights. I spoke with a technician from Stern who said it might be a bad PIA at location 11B. However, when I start the machine, the row of LEDs on the CPU lights in the proper sequence, indicating all the PIAs are in working order. This same system is used on Hook.

If anyone knows or has a clue as to what might be the problem I'd be most grateful to learn about it. Thank you to all who offer help.

Thanks for your reply. I understand your confusion. Upon powering the game up, the first row of lights is illuminated. Initially, no lights should come on until the start button is pressed. And once the pin is started for play all three rows should come on in a chase formation, rather than one row of lights constantly illuminated without a pulse. So, only two rows flash while the first row stays on without pulsing.

I didn't bother checking for a pulse because the first row doesn't pulse at all. Therefore, the output will not be pulsing. Furthermore, connection points CN1 and CN2 on the CPU are not used. There are no harnesses coming from those points. Perhaps there's something there you know that I don't. If so, I'd love to know more.

In conclusion, the PIA at position 8H has been replaced utilizing a new socket, which is not stock on this CPU. This tells me that there was some kind of problem prior to my purchasing this machine.

Again, thank you very much to all who respond. This problem is the most goofy and strange among the eight machines I own and have repaired.

Hi Richard,

Thank you so much for this information. I haven't had the chance yet to check the points you described, but I definitely will tomorrow when time avails. Also, your information on the PIA test LED clears up the confusion about the suspect 11B chip. I'm confident that testing this chip will reveal the cause of the problem. I will let you know when I find out. Thanks again for helping me to see through this problem more clearly.