To add a timeout step in a Jenkins pipeline, you can use the timeout block provided by the Pipeline Utility Steps plugin.

Here's an example:

pipeline {
    agent any

    stages {
        stage('Build') {
            steps {
                // build steps go here
            }
        }

        stage('Test') {
            steps {
                timeout(time: 5, unit: 'MINUTES') {
                    // test steps go here
                }
            }
        }
    }
}

In the above example, the timeout block will wrap the test steps and will cause the pipeline to fail if the test stage takes longer than 5 minutes to complete.

You can adjust the timeout duration by changing the time and unit values. Other supported units include SECONDS and HOURS.