Your child tax credit would be applied before your EV credit so you might be losing EV credit but you should not be losing child tax credit if your tax liability is less than $11,500 before credits. Please ignore your refund. What is your tax liability before credits are applied?
Also please understand that TurboTax 2018 is not yet fully functional. Neither the electric vehicle credit section or the child tax credit section is ready.yet and so any attempt to enter those credits may not work. If you are trying to do it on 2017 software, the child tax credit amounts, standard deductions, personal and dependent exemptions, and tax tables are all different in 2018
