Hands Free Phone
The Bluetooth® Hands Free Phone (also known as the Blue&Me™ Bluetooth® phone system) relies upon Bluetooth® technology to enable wireless connectivity between Bluetooth® compatible, paired and turned ON mobile devices and the on-board entertainment system components. This system also relies upon Advanced Speech Recognition (ASR) software to enable voice commands to control the mobile device as well as the components and features of some other on-board systems.
The system will recognize up to five Bluetooth® compatible devices, each of which is identified within the system by the name acquired from the device during the pairing process. The Hands Free Phone system will communicate with a paired device that is anywhere within the vehicle; however, covering the paired device with a metal object may block the signal. Also, only one device can be connected at a time. If multiple devices are registered, at ignition ON the system will automatically connect to the last device that was connected before ignition OFF.
The Hands Free Phone system is operated in one of two ways: actively or passively. Active operation begins with the vehicle operator pressing a push button in the steering wheel switch pod on the face of a horizontal spoke of the steering wheel. The Blue&Me™ Voice Recognition button is pressed for hands free voice command access to available features other than the phone, or the Blue&Me™ Phone button is pressed for hands free phone access.
The VR or Phone button press provides a resistor multiplexed input to the Body Control Module (BCM). The BCM is a gateway to the Controller Area Network (CAN) - B data bus and sends an electronic switch press message over the CAN-B data bus to the Radio Receiver Module (RRM). The RRM also sends electronic messages over the CAN-B bus to the Instrument Panel Cluster (IPC) to display the appropriate text messages within the Electronic Vehicle Information Center (EVIC).
When the RRM receives the electronic switch press message, the RRM suppresses any current audio output and issues an audible beep to indicate that the VR hardware is prepared to receive a voice command. Part of the Bluetooth® Hands Free Phone system hardware includes the VR microphone integral to the courtesy lamp unit in the headliner centered between the sun visors near the windshield. The microphone provides a hard wired input of voice commands to the VR engine within the RRM, and the ASR software converts that input into an electronic instruction message broadcast over the CAN-B data bus to invoke the appropriate system response. If no appropriate voice command is received within a few seconds following the audible beep , the system will provide an audible verbal output listing a menu of the available Voice Recognition options.
Passive operation begins when an incoming cellular call is received. If the Bluetooth® phone is Short Message Service (SMS) text message capable and compatible with the Bluetooth® phone system, passive operation will also begin when an SMS text message is received. The call or SMS text message is relayed to the Bluetooth® transceiver embedded within the RRM. The Bluetooth® transceiver then instructs the RRM to announce the incoming call or message. The vehicle operator presses the appropriate Bluetooth® Phone button in the steering wheel switch pod to accept or reject the call or the message.
The Bluetooth® transceiver connects the voices of the two phone parties using outputs through the audio system speakers and inputs through the Bluetooth® hands free microphone. In the case of a text message, the Bluetooth® transceiver sends the message to the VR hardware and the ASR software converts the message from text to voice and plays it through the audio system speakers. The text message can then be replied to by depressing the Bluetooth® VR button and giving an SMS voice command to select from several predetermined short text phrase responses.
The Hands Free Phone system operates on battery current received through a fused B(+) circuit, but also monitors the ignition switch status through electronic messages received over the CAN-B data bus. If a call is in progress when the status of the ignition switch transitions to OFF, the system will continue to operate until the call has been completed.
The RRM receives electronic message inputs over the CAN-B data bus related to the Hands Free Phone system. The RRM is also connected to the CAN-C data bus; however, the RRM is not a CAN gateway. All electronic message outputs of the RRM are carried over the CAN-B data bus. When the RRM monitors a problem in any of the Bluetooth® transceiver circuits, it stores a fault code or Diagnostic Trouble Code (DTC) in its memory circuit.
The hardwired circuits between components related to the RRM and the Hands Free Phone system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds. For proper wire repair, and connector repair procedures. Refer to STANDARD PROCEDURE and Refer to REMOVAL and Refer to INSTALLATION .
However, conventional diagnostic methods will not prove conclusive in the diagnosis of the RRM or the electronic controls and communication between modules and other devices that provide some features of the Hands Free Phone system. The most reliable, efficient and accurate means to diagnose the RRM or the electronic controls and communication related to Hands Free Phone system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.