LifeFitness LifeRower 9500 powers up but freezes on boot up?

Just picked up this unit on ebay.

It would not power up at all, found that the main fuse was blown...Replaced.

Powered up (screen lit up, pcb led flashed) and ran the program for 2min till it froze.

Then would not run the program at all till I pulled the plug and let it sit for 5min, now it powers up boots and freezes almost straight away or sometime does not boot at all.

Back up battery on PCB was dead and leaking so I removed and cleaned PCB. Still having same booting issues. Any help would be great.