RCS not always firing

[Clipperride]

Do probe cores ever automatically fire vernier engines?

I'm currently putting some mining equipment on Minmus and so I am taking some fairly large payloads. My problem is the RCS and vernier engines don't fire on the payload stage when I use one of the buttons next to the NAV ball to hold position. If, for example, I change from retrograde to prograde by simply clicking on the symbol, the ship won't budge. I can manually steer the ship but even then it will drift from the set attitude.

I've added vernier engines to move things about on Minmus, but these don't fire when I change from one attitude to another. Again all is fine if I move things manually. Is it just that the probe core is just trying to use regular RCS clusters and ignoring the vernier's? The vernier's do fire when I turn the SAS off then on and the ship is rotating. They bring it to a stop, but won't change its heading.

Edited September 17, 2015 by Clipperride

[cephalo]

Verners use lfo fuel instead of monoprop. Is that the problem? Another problem can be that if there is too much control authority, SAS just can't handle it.

[Zephram Kerman]

Could be a glitch. I've noticed weird behavior from my RCS system on one ship. It's very intermittent and random, so I can't describe it well enough to write a bug report. Seems to be related to power not always reaching the probe core and having a low-level pilot standing by. To get around it, I make sure the probe is powered and in control, then switch vessels to reset everything.

[Clipperride]

I can get the vernier's to fire when I manually turn, so there's fuel and power. I'll double check the alignment of my thrusters in case that's the problem.

[jiminator]

I used the tiny square probe core... and I had no control on anything. not sure what happened there, so I just fired engines near retro to bring it home.