Jandy PCB 8124A Power Center is the main control board for Jandy AquaLink pool and spa systems, handling motor drives, pumps, heaters, and user interface signals. Common faults include a dead power supply or blown regulator on the 12‑V rail, burnt capacitors or diodes in the high‑current relay section, and cracked solder joints around the 52‑pin connector that cause intermittent communication with the C22.2 serial adapter. For troubleshooting, first verify the 12‑V and 24‑V rails at the board’s input terminals; then inspect for visible component damage or overheating on the power/relay circuitry; finally check the serial line voltage and continuity to the C22.2 adapter while monitoring any error codes displayed on the pool control panel.[oss-gpt-20b]