Why does my optimized idle not work reliably?

Are you putting it into optimized idle in the front first?

 

What is your current temperature, external/internal? And company truck or o/o?

 

Should know your external temperature, check the dash. My suggestion would be to contact your shop guys ASAP in the AM and see if something might be wrong in the programming.

 

Hopefully it keep going all night. When you say a/c stops after 15 minutes do you mean the engine a/c or the electric a/c ? They work together. If you turn on Interior Comfort Mode. The computer will start the engine and use the regular engine a/c to cool the truck. Then it will shut engine off and the electric a/c in sleeper will turn on and cool the sleeper again

If the batteries get low for the electric a/c it should start engine to recharge batteries and cool the sleeper again with engine a/c for 2 hours to recharge the batteries.

If not getting good air flow from sleeper vents the air filter might need to be cleaned