The six-time IndyCar champion came up short of victory in Monday’s race, losing to teammate Alex Palou.
Dixon looked like he might win the 100-lap race after opting for an alternative strategy that put him at the head of that queue.
However, Palou pulled off an undercut and usurped Dixon for the effective lead of the race.
Dixon, meanwhile, pitted a lap later and struck traffic on his in-lap.
Speaking post-race, the New Zealander revealed a radio failure meant he was making the call to pit himself.
“That was frustrating,” said Dixon.
“We had no radio. So I was just flying blind out there and ultimately I think they were trying to call me in because on that last lap before we pitted, there was just so much traffic and we lost two or three seconds and that’s where the #10 car got us.
“Definitely frustrating. I think we had the speed. We had a great car. I think the pit stops were fantastic. Just would have been nice to have a radio so I could have known what was going on out there.
“Kudos to the #10 car and congrats to Chip and everybody on the team, the PNC Bank #9, Honda did a fantastic job, especially with fuel mileage. Frustrated man. I thought we really had that one and we came up short.”
Dixon said he was driving to the light on his dashboard, which let him know when he was running low on fuel.
“You’re out there by yourself of course, but when there’s no radio to talk to, even fuel mileage,” he explained.
“You’re not sure if you’re making the mileage to get to the next window. What’s happening even with our spotters or anything like that.
“It’s definitely tough to run a full strategy and a full race like that to make sure you’re running off just a fuel light to see that you’re going to get into the pits. Ultimately, it cost us the race.”
