Axon AX100 MK2 booting erraticaly -- battery?

[noceguitars]

Hi everyone,

I'm servicing this Axon and got it to power up. However it takes about 5 power cycles to boot properly. The first and maybe second time it won't boot at all, stuck in the "AXON" screen. Then for the next one or two it boots but halts shortly thereafter. And finally in the next one it starts and works fine.

After it boots as it should, while the AC adapter is connected it will boot normally every time. However, if it's off for a long period and AC disconnected, the weird boot sequence starts again.

Looking at the boards I see no CMOS battery like earlier Axons used to have (I once serviced a NGC77).

Am I missing something? Is there a battery in disguise somewhere?

Thanks!

[Elantric]

Common fault symptoms of weak /failing electrolytic capacitors in the power supply

If you have an Oscilloscope,  weak capacitors exhibit AC ripple on DC Power rails

New electrolytic capacitors in the power supply should remove the AC ripple current , and restore normal operation.

Other strategies

[noceguitars]

Very helpful, @Elantric. Thanks a lot!