Joseph Marshall declined the offer of a fixed penalty notice after being stopped by police in Innerleithen.
But he told this week's Justice of the Peace Court in Peebles that he was guilty.
He said: "I had the phone in my hand as I was going to plug it into the bluetooth. It doesn't work unless it's plugged in as it fell off a roof and the handset doesn't work properly."
Marshall, who already has a previous offence for driving while using a phone, was stopped by police just before 9am.
Procurator Fiscal Depute Tessa Bradley said: "Police were on patrol when they saw Mr Marshall driving a white van with a phone in his hand."
Justice of the Peace Fiona Ballantyne placed three points on Marshall's licence and reinstated the £60 fixed penalty.