Cannot access Siri Eyes Free from the switch on the steering wheel

Symptoms

["Check if a Bluetooth connection is established between the iPhone and the system.", "Check if Siri is enabled on the device. On your phone, go to Siri setting.", "Check that Siri can be accessed from the device lock screen. This can be set in the settings menu of your phone.", "Models without navigation system: Check the settings for Siri Eyes Free activation on the vehicle audio system. If the setting is “Long Press”, you must push and hold the TALK switch on the steering wheel for more than 1.5 seconds to start Siri Eyes Free. If the setting is “Short Press”, a short push and release of the switch should start Siri Eyes Free."]