If you have another monitor, I'd give it a try. Also, if you have another monitor cable, I'd try that as well as I'm assuming the Playstation uses a different connection to the monitor.
How long have you run the PS on the monitor?
The repair depends on what's broken and you have to open the monitor up and do board-level diagnostics to find that. If its a cheaper monitor, it probably isn't worth repairing.
Let me know what you find.
Sr. Network Engineer
A+, MCP, MCSE, 15 years of experience