Need help with "out of command range" situation

[Husky]

If my unit is out of command range (surrounded in red) and doesn't get the leadership from HQ does that mean all unit checks will fail or no checks at all?

[Joel Billings]

You won't have no chance of passing the leader rolls, but the chances will be reduced due to being out of command range. The further the distance, the less the chance to pass the leader check. At it's most basic, if you have a 5 leader value and are within 5 hexes of your corps command (for Axis), you've got a 5/10=50% chance to pass the test. If you are 10 hexes from the corps HQ you have a 5/(10+10-5)=33% chance. If you are 25 hexes away, then it's 5/(10+25-5)=16%. Of course you also have a chance of having higher level HQs pass the check for the unit. They are also impacted by range, but it gets more complicated to calculate.

[homer82]

If my unit is out of command range (surrounded in red) and doesn't get the leadership from HQ does that mean all unit checks will fail or no checks at all?

It's not quite that bad but there is a penalty for being out of command range. See 15.5.4 of the manual.