Location of ECS CodeDeploy logs?

CodeDeploy logs is not supported for Amazon ECS deployments nor AWS Lambda.

Specifically, there is no application related deployment commands executed by CodeDeploy as your application is packaged as a container, and the configurations are drafted in ECS task definitions so CodeDeploy logs won't have much value compared to traditional deployments to EC2.

that said, you can view deployment related events in services such as ECS, or in CloudTrail.

Is there anything specific you are looking for in the log?

Per the documentation:

Logs are not supported for AWS Lambda or Amazon ECS deployments. They can be created for EC2/On-Premises deployments only.

In lieu of logs, I recommend creating a subscription via EventBridge to CodeDeploy-related events as described here. You can configure CloudWatch Logs as an event target, and this will create an indirect log of your deployments.