2014 Jeep Wrangler JK Factory Service Manual 08 - Electrical

MODULE, Hands Free (HFM)

DESCRIPTION


The Hands Free Module (HFM) (1) (also known as the Bluetooth™ module) is found in vehicles equipped with the optional Uconnect® Hands Free Phone System. This module is located on a bracket of the instrument panel support structure behind the instrument panel center bezel. The HFM hardware and circuitry is contained and protected within a molded black plastic housing that has two integral mounts (4). The HFM is secured to the bracket by two screws.

The HFM has three integral connector receptacles that are oriented toward the dash panel when it is installed in the vehicle. The two largest receptacles (2) connect the HFM to the vehicle electrical system through dedicated take outs and connectors of the instrument panel wire harness. The smallest connector (3) accepts a Universal Serial Bus (USB) cable connector that connects the HFM to the Radio Receiver Module (RRM) (also known as the radio or the head unit).

The internal circuitry of the HFM includes a microcontroller, flash memory and a Bluetooth™ module. The module also includes sophisticated Voice Recognition (VR) software. The HFM software is flash programmable.

The HFM cannot be adjusted or repaired and, if damaged or ineffective, the entire HFM must be replaced.

OPERATION

The Hands Free Module (HFM) (also known as the Bluetooth™ module) is used only in vehicles equipped with the optional Uconnect™ Hands Free Phone System. The HFM contains the microcontroller, logic and memory circuits of the Hands Free Phone System. The HFM uses On-Board Diagnostics (OBD) and can communicate with other electronic modules in the vehicle as well as with the diagnostic scan tool using the Controller Area Network data bus. This method of communication is also used for Hands Free Phone System diagnosis and testing through the 16-way data link connector located on the driver side lower edge of the instrument panel and is used by the HFM to acquire vehicle configuration data.

The HFM brings together several technologies in the vehicle. The HFM uses Bluetooth® technology to provide wireless connectivity between a paired compatible personal cellular telephone or a paired personal wireless audio streaming device and other on board vehicle systems. The HFM also uses sophisticated Voice Recognition (VR) software to recognize and respond appropriately to certain verbal commands, which allows hands free control of a number of optional vehicle systems and features. In addition to English, the VR software includes Spanish and French language capability. Incoming call voices are broadcast through the front audio system speakers of the vehicle, automatically overriding any other audio signals on the front speakers while the Hands Free Phone is in use.

The HFM circuitry receives battery current through a fused ignition output (unlock - run - start) circuit and fuse through the Totally Integrated Power Module (TIPM). The HFM also has a path to ground at all times received through a ground circuit and take out of the instrument panel wire harness that is secured to the body sheet metal. These connections allow the HFM to operate whenever the status of the ignition switch is Unlock, Run or Start. Other inputs to the HFM include:

Outputs of the HFM include:

The HFM uses On-Board Diagnostics (OBD) to monitor all of the systems and circuits it controls, then sets active and stored Diagnostic Trouble Codes (DTC) for any monitored system faults it detects. The HFM will also send electronic message requests to the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN) for the display of certain textual warning messages related to some detected system conditions or faults.

The hard wired circuits of the HFM 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 or the electronic controls and communication between modules and other devices that provide some features of the Uconnect™ Hands Free Phone system. The most reliable, efficient and accurate means to diagnose the HFM or the electronic controls and communication related to Uconnect™ Hands Free Phone system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

DIAGNOSIS AND TESTING - HANDS FREE MODULE

The hard wired circuits of the Hands Free Module (HFM) (also known as the Bluetooth™ module) 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 or the electronic controls and communication between modules and other devices that provide some features of the Uconnect™ Hands Free Phone system. The most reliable, efficient and accurate means to diagnose the HFM or the electronic controls and communication related to Uconnect™ Hands Free Phone system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

REMOVAL

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.


  1. Disconnect and isolate the negative cable from the battery.

  2.  
  3. Remove the center bezel (1) from the instrument panel. (Refer to 23 - Body/Instrument Panel/BEZEL, Instrument Panel - Removal) .


  4.  
  5. Remove the two screws (2) that secure the Hands Free Module (HFM) (1) to the instrument panel support structure.

  6.  
  7. Pull the HFM away from the instrument panel far enough to access and disconnect the instrument panel wire harness connectors from the HFM connector receptacles.

  8.  
  9. Remove the HFM (1) from the vehicle.

  10.  

INSTALLATION

WARNING:

To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.


  1. Position the Hands Free Module (HFM) (1) close enough to the instrument panel to access and reconnect the instrument panel wire harness connectors to the HFM connector receptacles.

  2.  
  3. Position the HFM to the instrument panel support structure.

  4.  
  5. Install and tighten the two screws (2) that secure the HFM to the instrument panel support structure. Tighten the screws securely.


  6.  
  7. Reinstall the center bezel (1) onto the instrument panel. (Refer to 23 - Body/Instrument Panel/BEZEL, Instrument Panel - Installation) .

  8.  
  9. Reconnect the negative cable to the battery.

  10.