[DG] [DG11] Drivestop issue

[billgcroton]

Hello,

I have a circa 1986 autopilot with certain upgrades having been made in the interim.

Type 300 Course Computer -- original
Rudder sensor-original and works fine
Fluxgate compass replaced about 5 years ago.
ST6000+ (upgraded about 10 yrs ago).
Type II linear drive

---Clutch operates fine when engaging auto, but pilot does not steer (pressing +10 and -10 results in DRIVESTOP error.

I am getting 12V at the Power input to the 300
I am getting no response when I connect the MOTOR wires to 12V (both directions).
I am getting only around +/- 7.5 volts at the MOTOR terminals on the 300 when pressing +10 and -10.

So the drive motor seems to need service, but the 300 Motor output seems to be under volt.

What other troubleshooting tests should I do before deciding what to do next?