ST4000+ Autopilot Low Batt

[jonelli]

After putting in the "Catalina Cocktail" it amazingly steers like magic now.
But every couple of minutes it beeps and complains with a low batt message.
I've done a few tests, with engine running, on shore power, engaged to wheel, disengaged from wheel, and still low batt message no matter what.

I haven't pulled the main head unit out yet to check all the connections and wiring, but that's my first place to check. I found a guy on Ebay that repairs them for about $150 if needed. Ebay user: kodiakjack99

 

[seanshine]

I don't know how you wired yours, but the 4000 is supposed to be wired directly to the battery. SS

 

[jonelli]

I didn't wire it. It came with the boat last year.
I have a master switch for Autopilot and GPS power on my panel that isn't factory default someone added to it.

Assuming that it worked at some point in the past, its either a corroded bad connection problem with low voltage, or a bad head unit. That's my theory.

I'll start by tracing out the wires from the battery/panel to the cockpit, then I'll have to figure out how to get the head unit out to check it's connections. It looks like there's two studs with nuts on them behind the whole thing. Cant really get my head back there to see anything, I'm assuming the only way to get in there is through the rear locker in the cockpit...

 

[PineyWoods]

The twist-lock plug in to the wheel motor has been the most vulnerable connection in my past several units. It's not really very secure, and if the rubber boot is loose, susceptible to corrosion.

Also, be sure that there's a 10 amp. in-line fuse wired into the pos. circuit somewhere before the control head. I learned the hard way once depending on the panel circuit breaker to protect the head after the motor eventually failed, shorted out, and drew too much current through the head and blew it also. My spare motor was useless.

Regarding a direct battery connection, you've got to have a switch in the system somewhere, and all of mine have been on a dedicated panel AP switch, except my "new" c30 that has all instruments on a single switch.

Pete

 

[jonelli]

Thanks for the tips. I haven't been back to check the motor end or remove the head unit. But, I did verify that the main power wire goes straight to my 1/2/B switch direct to the battery cable. It has an inline fuse and a single switch. Those connections look good. I'll check the motor this weekend, but pulling the head unit may have to wait awhile.