Autopilot control upgrade

[lyleh]

I have an older (mid 1990’s) Hunter P42 with original St50 instruments and ST6000 autopilot. It all still functions well except the type 100 course computer just developed a “low battery” issue and will not engage the autopilot. I have done extensive testing and the unit is getting good voltage even under load so it isn’t a connection issue. Apparently this is an issue with some older Type 100 units. I can find a replacement Type 100 course computer on EBay which would be the easiest and cheapest solution but am thinking of upgrading the course computer and autopilot control head but keeping the original Type 100 hydraulic drive and rudder position indicator. The question is whether the new Raymarine electronics will connect to and function with the old St50 seatalk instruments.

 

[jssailem]

The concept is sound. But I would contact the Raymarine Technical support with the serial number and model of your hydraulic drive to verify that it will work with their new computer.

 

[DougM]

Do the ST6000 -6001 course computers have a backup battery on the motherboard?
If so, that could be the battery that is “low” or dead

 

[jssailem]

100 course computer just developed a “low battery” issue and will not engage the autopilot.

The manual identifies this issue on page 26 of the manual.

Low battery
LOW BATT
The Low Battery alarm sounds when the supply voltage drops below acceptable limits.
Press standby to clear the alarm and return to hand steering. Start the engine to recharge the battery.

The batteries in question are the boat battery used to power the system.

This fault could be the battery itself ( low voltage) or you could have corrosion on the connections/wires powering the unit. Corrosion will cause a voltage drop. Low voltage is interpreted by the ACU as a “low battery “.

 

[Rick D]

FWIW, my Autohelm course computer started failing. I found a guy who repairs them. Sent it to him on a fixed cost basis and he fixed it. He says about 80% are repairable. I got a used on e-bay but it failed soon after the install. I just sent that unit back to him to keep as a back up. He reported it was successfully repaired. Here is his (Dan's) e-mail address: c250@mydurango.net

 

[dlochner]

How old are the batteries? If they are older or not at full capacity when a load is placed on them the voltage will drop precipitously which might trigger the alarm. This can happen even when the resting voltage of the battery is at a normal level ~12.5v. It is not the voltage per se that is the issue, rather it is the ability of the batteries to provide sufficient amperage to drive the hydraulics.

One easy test is to try the AP while under power so the current is coming from the alternator.

 

[Stu Jackson]

FWIW, my Autohelm course computer started failing. I found a guy who repairs them. Sent it to him on a fixed cost basis and he fixed it. He says about 80% are repairable. I got a used on e-bay but it failed soon after the install. I just sent that unit back to him to keep as a back up. He reported it was successfully repaired. Here is his (Dan's) e-mail address: c250@mydurango.net

I can attest to Dan's credibility. He repaired my ST3000 which broke on the way up from SF to BC, outside Newport, OR. It was fixed and awaiting me when I got here. Great guy, great service.

 

[Claude L.-Auger]

Ditto for me Dan repaired my ST-60 Windmeter a few years back and it has been working flawlessly since. Wonderful and charitable guy as well. At the time he did my repair, he was involved with some charity organisation for kids in Mexico where he had his boat. He asked me to forward the payment to them and send him a copy of the receipt. I thought this was amazing.

 

[lyleh]

Thanks for the replies. It’s not a battery issue and I have tested the voltage under load so a connection is not the issue as far as I can tell. I will contact Dan to try to repair it.