ST4000 MK1 not powering up

[patrickkidd]

Hello! I have an old black ST4000 MK1 and the unit only powers up every 10th-15th flip of the power switch. The unit came with the boat which I bought last year.

I bought an identical replacement control unit on eBay because the display of my original was also dying, and found that it did the same thing. On each flip of the switch where it didn't turn on, the speaker sent out a constant tone, the display was blank, and the motor would turn until it reached the end of it's travel. On each successful flip of the switch the speaker would beep once and the display would turn on. Now the speaker has stopped making sound at all and I have to jump into the cockpit to see if the display is on after each switch - quite cumbersome.

If my power source and wiring is good, is this a known issue on older units? Is there something else I can do?

Thanks!