FIDIC contracts usually mention "make good" a failure or defect or "remedy" it. In Sub-Clause 15.1 [Notice to Correct] both words are mentioned in the requirement of the notice to correct the Engineer is entitled to send to the Contractor.
They may appear to have the same meaning, but it is obvious from the wording of Sub-Clause 15.1 that they are intended to have different meanings. The dictionary definition of both words are (COBUILD advanced English dictionary):
If you make good some damage, a loss, or a debt, you try to repair the damage, replace what has been lost, or repay the debt.
If you remedy something that is wrong or harmful, you correct it or improve it.
It is apparent from the definitions that remedy is meant to correct the error or default (for example decrease its chances of happening again), while make good is meant to undo the damage or loss caused.
For example, if at a construction site, a worker, sadly, fell to his death from a high location. Here making good the damage means to resurrect the worker, which is not possible. However, possible remedies could include more strict HSE provisions for working at high locations.
Similarly, if a contractor installs a defective equipment, he may need to remove it (remedy) and install another working one (make good).
Therefore, it is implied that an Engineer cannot send a Notice to Correct in accordance to the provision of Sub-Clause 15.1 whereby a defect or default by the Contractor could not be both remedied and made good.