Hello Carol thanks for posting here in Community!
We don't have a link which we can direct you to with regards to recording a journal entry for personal use of a company car.
We would suggest with an accountant for this query, there may be an accountant user on Community who are able to answer this question for you. Please let us know if you have any further QuickBooks Online questions.
Hi @carolcurrier101 let me offer some insight. When a company car is used for personal use that use becomes non deductible for business purposes. If you use a flat mileage deduction rather than actual expenses it becomes relatively easy to calculate percentage of miles driven personal vs business but even that calculation can be used against actual vehicle expense to reduce what the business can deduct.
Another consideration is that providing a car to an employee for their personal use may be a taxable fringe benefit and would have to be included in their gross pay.
As complicated as it can be I echo the suggestion you discuss this with an accountant