Got a Jokerz in from a customer who had just installed LEDs in the game. Before the LEDs it was working fine, now it gets the "ADJUST FAILURE" message. I'm not sure how the two could possibly be related but I'm not a big believer in coincidences. Anyway batteries are good so I tried to do a factory reset. I get to the factory reset setting, choose yes, then boom ADJUST FAILURE again. I would think that even if there was a problem with the batteries / battery holder / related circuit that I should still be able to do a factory reset, it would just be lost after cycling the power. I should also mention that as I was cycling through the settings I couldn't change most of them; the credit button did nothing. Not sure if that's relevant but it's definitely not normal.
Next step was to replace U25 with a 6116 version anyPin NVRAM that I had laying around. No help, exact same symptoms with the anyPin. So basically I'm seeing the ADJUST FAILURE message on power up and again as soon as the game tries to write to U25. Any ideas where to look next?