Hands Free Phone

WARNING: This page is about a different car, the 2016 Jeep Wrangler and 2015 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.

The Uconnect™ Hands Free 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 ten 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.

The Hands Free Phone system is operated in one of two ways: actively or passively. Active operation begins with the vehicle operator depressing a push button in the Electronic Vehicle Information Center (EVIC) switch pod in the left horizontal spoke of the steering wheel. The Uconnect™ Voice Recognition (VR ) (also known as Voice Command) button is depressed for hands free Voice Command access to available features other than the phone, or the Uconnect™ Phone (Phone is identified by a phone handset icon) button is depressed for hands free phone access.

The VR or Phone button press provides a resistor multiplexed input to the Steering Control Module (SCM) in the right (also known as the speed control) switch pod. The SCM sends a switch status message over the Local Interface Network (LIN) data bus to the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN). The EMIC is a gateway to the CAN - Interior High Speed (CAN-IHS) data bus and sends an electronic switch press message over the CAN-IHS data bus to the Hands Free Module (HFM) (also known as the Bluetooth™ module) and the Radio Receiver Module (RRM) (also known as the radio or the head unit).

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 within the HFM is prepared to receive a Voice Command. Part of the Uconnect™ Hands Free Phone system hardware includes the VR microphone integral to the driver side upper A-pillar trim. The microphone provides a hard wired input of Voice Commands to the VR engine within the HFM, and the ASR software converts that input into an electronic instruction message broadcast over the CAN-IHS 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 Command 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 Uconnect™ system (see the Uconnect™ web site), 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 Uconnect™ Phone button in the steering wheel switch pod or the soft button that will appear in the RRM display to accept the call or to accept the message.

The Bluetooth™ transceiver connects the voices of the two phone parties using outputs through the audio system speakers and inputs through the Uconnect™ 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 Uconnect™ 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-IHS 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-IHS 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-IHS data bus. When the HFM or the RRM monitors a problem in any of the audio system circuits and components, or in any of the Bluetooth™ transceiver circuits, it stores a fault code or Diagnostic Trouble Code (DTC) in its memory circuit.

The hard wired circuits between components related to the HFM, 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, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the HFM, 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 HFM, 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.