2015 Acura TLX Base, 2.4L EngFACTORY OEM SERVICE PROCEDURE

Unit Check

Some of the tests and screens that are displayed under the Unit Check are different from the more detailed checks listed under other menu options.

To start the test, select the item you want to check.

  • ECU Info
  • Display
  • SiriusXM
  • CD Mech
  • B-CAN
  • COMPASS
  • GPS
  • Remote Tuner
  • HFL
  • Rear Camera
  • Mic/STRG
  • USB
  • Car Status
  • Speaker Check
  • Hard Key
  • CarPlay Box
GHH195594Courtesy of HONDA, U.S.A., INC.

ECU Info 

This screen displays for information in the audio ECU.

  • Serial No.: Displays the audio unit serial number. That should be the same as the serial number found on the upper side of the audio unit.
  • Coverage: Displays the destination market of the audio unit.
  • Model: For this vehicle and trim level, the field should begin with TZ3.
GHH195595Courtesy of HONDA, U.S.A., INC.

Display 

This diagnosis does additional checks on the GA-Net bus between the audio unit and the center display unit. This test also checks the internal electronic functions.

  • If Connection shows NG, the GA-net bus connection may be open or short between the center display unit and the audio unit.
  • Version: Displays the center display unit software version.
  • If ROM or RAM shows NG, replace the center display unit .
GHH195596Courtesy of HONDA, U.S.A., INC.

SiriusXM 

This diagnosis displays the SiriusXM status.

  • If GA-NET shows NG, the GA-net bus connection may be open or short between the tuner unit and the audio unit.
  • If Antenna shows NG, the connection may be open between the tuner unit and the roof antenna.
  • If RS485 shows NG, the RS485 connection may be open or short between the tuner unit and the audio unit.
GHH195597Courtesy of HONDA, U.S.A., INC.

CD Mech 

This diagnosis checks the audio unit internal CD player mechanism.

Version shows CD mech version. When the audio unit can read the version number, Connection shows OK. If the version number cannot be read, Connection shows NG.

  • Inserting the CD mech update disc allows you to select Download. Otherwise it is grayed out.
  • To update the CD mech, you must insert the update disc before selecting this screen. If you insert the update disc when you are on this diagnosis, the DownLoad stays grayed out. In this case, exit the CD Mech screen and start the diagnosis again.
GHH195598Courtesy of HONDA, U.S.A., INC.

B-CAN 

NOTE:  This diagnosis must have the engine running.

This diagnosis checks whether the audio unit has received specific B-CAN data. If ERROR STATUS shows NO ERROR, an error is not detected between the B-CAN bus and the audio unit.

  • If ERROR STATUS shows RAM ERROR, replace the audio unit .
  • If the audio unit detects the B-CAN data reception error, ERROR Status shows RX ERROR.
  • If ERROR STATUS shows TIME OUT, There is a possibility that some items are NG (red icon). When all the items from each transmitting unit is NG, check for B-CAN DTCs with the HDS. If DTCs not detected, check for continuity in the B-CAN lines between the audio unit and the transmitting unit.
GHH195599Courtesy of HONDA, U.S.A., INC.

COMPASS 

This diagnosis checks the electrical compass unit connection.

GHH195600Courtesy of HONDA, U.S.A., INC.

GPS 

This diagnosis checks the GPS antenna connection and the GPS receiver condition.

  • If Antenna shows NG, the connection may be open between the GPS antenna and the audio unit.
  • If Receiver in Navi ECU shows NG, replace the audio unit .
  • Select Information to see the GPS satellite details.
GHH195601Courtesy of HONDA, U.S.A., INC.

Remote Tuner 

NOTE:  For factory use only. Do not alter any settings unless directed.

This diagnosis shows the external radio tuner (AM/FM) status. Make sure the audio unit radio tuner is turned on and the AM or FM source is selected.

  • Current Frequency can be changed by selecting TUNE.
  • Source can be changed in this order: AM→FM by selecting Change.
  • Electric Field Intensity: Displays radio reception sensitivity (dBμV).
  • ANT +B: Changes the AM/FM antenna power status ON or OFF.
  • RDS BER: Displays the number of RDS error that is receiving.
  • F-Check: Changes the station list automatic updating operation status ON or OFF.
  • Antenna: If the vehicle has diversity antenna, you can select the radio antenna function from Auto, Main, Sub, or PD (diversity).
  • Version: Displays the tuner unit software version.
  • Serial No.: Displays the tuner unit serial number.
  • Part No.: Displays the tuner unit parts number.
  • Database Clear: The Station list in the tuner unit can be cleared by selecting Clear.
  • HD Radio: Changes the HD Radio (TM) function status YES or NO.
  • RS485: If RS485 shows NG, the RS485 connection may be open or short between the tuner unit and the audio unit.
GHH195602Courtesy of HONDA, U.S.A., INC.

HFL 

This diagnosis checks first whether the HandsFreeLink control unit is connecting to the audio unit via the GA-Net bus.

Check any official Honda service website to see if there are any updates available for the HandsFreeLink control unit. If the HandsFreeLink control unit need to update the software, do the HandsFreeLink Control Unit Update .

GHH195603Courtesy of HONDA, U.S.A., INC.

Rear Camera 

This diagnosis checks the rearview camera connection.

  • If Connection shows NG, the connection may be open between the rearview camera and the audio unit.
  • If Connection shows OK, press the SETTINGS button to display the rearview camera image. To return to the previous screen, press the SETTINGS button again.
GHH195604Courtesy of HONDA, U.S.A., INC.

Mic/STRG SW 

This diagnosis checks whether the microphone is connecting to the HandsFreeLink control unit, and checks whether the HFL switch is communicating with the audio unit.

When STRG SW shows OK, press the PICK-UP, HANG-UP/BACK, and TALK buttons. As each button is pressed, the corresponding icon on the display should turn green.

GHH195605Courtesy of HONDA, U.S.A., INC.

USB Memory Information 

NOTE:  Not all USB memory drives are compatible. See the Owner's Manual for more information.

This diagnosis displays the USB memory device status when a USB memory device is connected to the audio unit.

If a USB memory device is connected to the USB port, the screen displays the connection status (Inserted/Not Inserted), the USB memory size, and the Product ID, Vender ID.

GHH195606Courtesy of HONDA, U.S.A., INC.

Car Status 

Use this screen to confirm that the audio unit is properly receiving input signals. The displayed value changes each time according to the state of input signal.

Item Input Description
VSP B-CAN lines
  • 1: When the vehicle speed pulse is received from the PCM
  • 0: When the vehicle speed pulse is not received from the PCM
BACK BACK LT line
  • 1: When the transmission is shifted to R position/mode
  • 0: When the transmission is shifted to any position/mode other than R position/mode
ILL B-CAN lines (from gauge control module)
  • 1: When parking lights, or headlights are on
  • 0: When parking lights, or headlights are off
ILL CANCEL B-CAN lines
  • 1: When the dashlights brightness control is more than 90 % brightness with the parking lights turned on
  • 0: When the dashlights brightness control is less than 90 % brightness with the parking lights turned on
PARK B-CAN lines
  • 1: When the parking brake is applied
  • 0: When the parking brake is not applied
VIDEO PARK * PARKING BRAKE SW line
  • 1: When the parking brake is applied
  • 0: When the parking brake is not applied
IGNITION B-CAN lines
  • 1: When the vehicle is in ON mode
  • 0: When vehicle is in ACCESSORY mode
ILL DUTY B-CAN lines (from gauge control module) With the parking lights on, use the dashlights brightness control to dim and brighten the gauge. The value changes from 1 (max low) to 22 (max high).
RECEIVED VIN NO B-CAN lines This item indicates the VIN that received from the PCM.
INTERNAL REGISTRATION VIN NO B-CAN lines This item indicates the initial registration VIN that is saved in the audio unit.
ADDITIONAL REGISTRATION VIN NO B-CAN lines This item indicates the additional registration VIN when the audio unit is substituted into another vehicle, or when a PCM is substituted or replaced into this vehicle.
GHH195607Courtesy of HONDA, U.S.A., INC.

Speaker Check 

NOTE:  While doing the diagnosis, the fader and the balance positions are set to the center.

This diagnosis checks the audio speakers individually.

Selects NEXT or BACK to select Speaker. A tone should sound from the speaker.

When you select NEXT, the system checks the speakers in this order: → → → → → → → →
When you select BACK, the system checks the speakers in this order: → → → → → → → →
  Display Message  Vehicle Test Condition 
FR L You should hear a tone from the driver's door speaker
FR R You should hear a tone from the front passenger's door speaker
RR R You should hear a tone from the right rear speaker
SWF You should hear a tone from the subwoofer
RR L You should hear a tone from the left rear speaker
FRTW L You should hear a tone from the left front tweeter
FRTW R You should hear a tone from the right front tweeter
ALL You should hear a tone from all speakers
GHH195634Courtesy of HONDA, U.S.A., INC.

Hard Key 

This diagnosis tests the interface dial, the center switch panel buttons that surround it, and the audio remote-HFL switch. For this model, the audio remote-HFL switch buttons use the BATT LIN data bus via B-CAN from the gauge control module for communications.

To complete the each test, control the audio remote-HFL switch, press the center switch panel buttons, and move the interface dial to each indicated position. As each function is tested, the corresponding button on the display should highlight. To exit, press in and hold the interface dial knob.

If the test cannot be completed, the corresponding icon on the Hard Key menu screen shows red.

  • Steering Key: Checks the audio remote-HFL switch buttons and the selector wheel.
  • Hard Key: Checks the center switch panel buttons and the interface dial.

NOTE:  You cannot use the onscreen return button to exit this function.

GHH195635Courtesy of HONDA, U.S.A., INC.

Select Steering Key 

GHH195636Courtesy of HONDA, U.S.A., INC.

Select Hard Key 

GHH195637Courtesy of HONDA, U.S.A., INC.

CarPlay Box (CarPlay and Android Auto Unit) 

This diagnosis shows the CarPlay and Android Auto unit status.

  • If CP/AA Connection and/or HDMI shows NG, the connection may be open between the CarPlay and Android Auto unit and the audio unit.
  • S/W Version: Displays the eMMC software version in the CarPlay and Android Auto unit.
  • Flash Version: Displays the Nor-Flash version in the CarPlay and Android Auto unit.
  • Serial No.: Displays the CarPlay and Android Auto unit serial number.
  • Mic Check: When you select Start, the system output mic sound.
  • Guidance Check: When you select Start, the system output test sound.
GHH195638Courtesy of HONDA, U.S.A., INC.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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