This will be a timer test.
We'll be testing the 555 timer "timeout" setting.
For this test:
1. 555 Pin #2 will need to be disconnected from 5v and reconnected to CD4013 pin #2
2. You'll need a stopwatch or timer to visually measure the timeout. (I use the timer on my iPhone)
3. We'll set the timeout to 10 seconds by adjusting VR1.
Begin test:
1. Cycle power off, then on, wait 1 minute.
After power up, only the Red LED should be "on".
2. Prepare your stop watch to time when the Yellow LED changes.
3. Press/release the button ONCE.
Yellow LED=on (the Grn LED will also turn on). Start stopwatch
Yellow LED=off at about 12 seconds (Grn LED also shuts off). Stop stopwatch.
4. If the time is longer or shorter than 12 seconds, re-adjust VR1, then repeat test from step 2.
Doesnt have to be exactly 12 second. Just consistent.
report back.