My st4000 wheel pilot turns on with the boat, rudders center up like normal, but then if I push the AUTO button the power fuse blows

The "Error Rudder" message on the C600AD display could indicate an issue with the linear feedback unit (LFU) or the rudder angle sensor. The LFU measures the position of the rudder and sends that information to the autopilot control unit.
You may want to check the wiring and connections between the LFU and the autopilot control unit to ensure that there are no loose or damaged connections. If the wiring is intact, the LFU may need to be replaced or recalibrated.
You may also want to check the rudder angle sensor to ensure that it is functioning properly. If the rudder angle sensor is not providing accurate information to the LFU, it could cause the "Error Rudder" message.
It may be helpful to consult with a marine electronics technician or the manufacturer of the C600AD autopilot system for further troubleshooting and repair recommendations.

I am not familiar with your particular model autopilot, but I do know that Raymarine autopilots can be fussy. All must have a compatible gps feeding it, of course. All must have a rudder angle indicator if your auto pilot connects to the wheel or rudder instead of directly to the tiller.

I’m happy to assist further over the phone at https://www.6ya.com/expert/bill_f6ca18ca1db028ed

Hi Alfred.

Your answer will depend on the fishing boat.
For really small boats, with an outboard motor on the back, the motor will be on a pivot joint, and have a handle in front. You point the running motor side to side to steer the boat.

Larger boats with outboards will have a steering wheel with a mechanical linkage to an outboard motor or motors that will pivot them side to side to steer.

Larger fishing boats, especially commercial boats, will have an inboard engine and prop shaft, a fixed external propellor or propellors, and a rudder that is connected with a mechanical linkage to the steering wheel or ships-wheel to move the rudder side to side and steer the boat by deflecting how the water flows by when under way.

Hoping this helps.

D

Has it ever worked?
What has changed?
Is it the a "pole/linear" or a "rotary" FB unit?
Out of the 5 basic parts of the AP system, the RFB is the most replaced due to the environment (Splash, heat, vibration, mech movemnet).

"Rudder feedback error"
does not see the RFB at all.
check the connections in the J-box first.
you should be able to manually turn your wheel and see the RFB indicator change on the control head.

"rudder responce error"
does not see the RFB move when the AP is given a command.
then check physical connections.
could be loose, could be backward?

what type of pilot?
Is there a rudder reference unit installed? if yes check rudder ref unit.
Does it does this only in auto?

Set standby and check if +10 and -10 pilot is turning in correct direction.If not See manual for installation drws and setup instructions.

What model autopilot? If it is a Raytheon/Raymarine try switching the motor leads to see if that works.

CHECK THE POWER SUPPLY WIRING ,If it worked before ,could be corrosion or lose wire connection,or terminal bad crimped,or terminal loose inserted.
If it is new installation ,power wires could be undersized,or battery discharged .
Normally autopilot shuts off from auto and restarts when power supply voltage drops under the reset voltage ,when the wheel turns ,the motor current increase and the power voltage drops when the power supply wires are not OK.

light on board is probably normal no, this is an inductive pickup, can not test with ohmeter, sorry. Test with display, observing rudder angle display. Do rudder setup repeatedly until it works, it is a little fussy for placement and clearance but patience and the correct "bracketry" will make this pilot perform great.

You would need to supply more info to pin point problem. 1) Do you have hydaulic steering?If so do you have a rudder feed back sensor. 2) Is this a new install or did the pilot work properly before 3) Do you have a smart pilot course computer in the system or is the wheel drive run straight from the head unit. 4)What was the deveation reading on your auto pilot compass when it was swang. 5)Was the pilot comissioned by a qualified person. I know there is a lot of questions here but there could be many things that are causing the S.Once the above questions are resolved I should be able to narrow it down to one or two things. Regards Robert

Remove all wiring from 4000 head, hook up only 12V, if seatalk fail continues, it is the head. if seatalk fail goes away, hook in instruments one by one until the bad head is found. Seatalk is 12V red, Ground Screen(bare wire) and Data yellow (pulsing voltage). good luck 847-746-0100 John Barry