Diagnosis
The system is in a flush cycle or error state. Alternating red/yellow indicates a communication error between the faucet base and the main unit's PCB.
How to Fix It
First, unplug the power adapter from the wall for 30 seconds. Then unplug the small DC connector from the back of the main unit. Wait 2 minutes. Plug the DC connector back in, then plug the power adapter into the wall. The system will reboot and the lights should sequence normally.
If That Didn't Work
The cable between the faucet base and the main unit may be damaged or loose. Trace the thin 2-wire communication cable. Ensure both ends are fully seated in their connectors at the faucet base and at the control board.
Heads Up
Do not ignore this. If communication is lost, the automatic shut-off valve won't function. The system could waste water continuously. Shut off the feed water valve until it's fixed.