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GROM BT3 Bluetooth FAQ

Check our most commonly asked questions below. Check the troubleshooting section for some common tips and solutions.

Fitment

Please check our compatibility guidefor your car make, model and year fitment and limitations.

Yes GROM Bluetooth adapter is compatible with your phone as liong as your phone has Bluetooth functionality. GROM Bluetooth car kit (GROM-BT3) is compatible with both Android and iPhone/iPod/iPad devices.

To install GROM Bluetooth to your factory car stereo you will need to take your stereo out. GROM Bluetooth car kit (GROM-BT3) connects to the back of your stereo to the extension or CD changer port that is located at the back of the stereo. You can install the Bluetooth car adapter yourself or you can ask help of the profeccional car stereo shop. Check out our Installs page for tips on how to install the Bluetooth car kits to your car stereo.

Standard GROM BT3 Bluetooth car kit includes: GROM BT3 main "brain" module, vehicle specific cable to connect to the back of the stereo, and omni-directional microphone with swivel mount.

Functionality

Yes the OEM factory hands free, if available, will keep working, when you install GROM Bluetooth car adapter.

Please check GROM compatibility guide for the information for your particular vehicle. In general external CD changer will be disconnected, if present. Built-in CD changer will keep working. Also SAT or XM radio might have to be disconnected if GROM Bluetooth car kit uses Satellite/XM emulation. Please check the product description and GROM compatibility guide.

The text is displayed on select text capable stereos.Stereos that support text include some BMW, Toyota, Lexus, Honda/Acura (in SAT mode), Mazda (in SAT mode), Subaru (SAT mode). Please check product listing for more detailed information.

  • CDC is CD Changer emulation. GROM Car Audio Kit emulates CD Changer, and you will use regular CD changer controls to change tracks/disks. CDC emulation is available for all GROM compatible cars.
  • SAT (or XM) stands for Satellite /XM radio emulation. Usually available for cars within United States. With GROM SAT Emulation you will use SAT/XM controls to control your device. Text will be displayed on SAT emulation compatible stereos. Stereo should be SAT/XM capable, but XM/SAT receiver has to be disconnected.
    • Please check product listing for more detailed information.

    If using only AUX and GROM Bluetooth car kit (GROM-BT3): to turn on AUX you will need to connect your device to AUX cable, turn off Bluetooth streaming, and turn on AUX device. Once you turn Bluetooth music streaming back on, you will need to turn the AUX device off, otherwise both will play at the same time.
  • If you use GROM Bluetooth car kit (GROM-BT3) with AUX cable and HD Radio Dongle (GROM-HDR1), the following will happen:
  • Bluetooth will always have the first priority. Once you start Bluetooth music streaming or phone call, it will go through the car stereo. Note that you will need to pause the aux device (if connected via 3.5mm phone jack cable) manually. No need to pause HD Radio.

    • You can activate Siri voice control by pressing Scan button twice. Please note that your phone should not be in Bluetooth audio streaming mode.

    Troubleshooting

    1. Press CD / AUX twice to enter cd changer mode
    2. Make sure factory external cd changer (if present) is disconnected
    3. Disconnect radio from power for 1-2 minutes. Do not forget to remember the Security code if any !
    4. Make sure red LED on Grom circuit board inside enclosure comes on with key. If LED light is not on, double check connections making sure everything is secure with no bent pins. If you have access to a multimeter check for power on pin 19 and 20 of Grom 20pin harness. There will be numbers on the white plastic
    5. Update to latest firmware version

    1. If your GROM is using SAT/XM emulation of your car stereo, you will need to make sure that you disconnected XM/SAT tuner. The tuner needs to be located and physically disconnected from car stereo for GROM car kit work in SAT/XM mode.
    2. Make sure red LED on Grom circuit board inside enclosure comes on with key. If LED light is not on, double check connections making sure everything is secure with no bent pins. If you have access to a multimeter check for power on pin 19 and 20 of GROM 20pin vehicle specific harness. There will be numbers on the white plastic
    3. If the P-Tap connection was used, make sure that everything is properly connected, and you were able to correctly tap teh GROM into the respective stereo connector. Refer to the connection manual that came with your GROM Bluetooth car kit.
    4. Refer to the manual that came with your GROM Bluetooth car kit to the information on how to activate the GROM mode on your particular vehicle.
    5. Update to latest firmware version
    6. If nothing helps - contact our tech support via Web Support Form or Live Chat

    1. Make sure volume is turned up on your device itself. Make sure that the Bluetooth volume on your phone is all the way up.
    2. Check all connections making sure they are secure, check to see if any change in sound if you wiggle the aux cable or apply slight pressure to 3.5mm side
    3. Check with different device to see if any change in volume

  • Make sure all connections are secure, double check ground wire if vehicle cable needed to be grounded
  • If using AUX, make sure AUX cable is connected securely and is not being blocked by device case
  • Wiggle AUX cable to see if any change, if good sound comes back, contact support

  • Double check that you applied the right firmware to the unit. If you apply Mazda firmware to your Toyota (for ex.) it will disable the device and you will need to apply the right update after you recycle power for GROM-IPD3 box
  • Then do the following steps:
  • Save the latest firmware for your car make on a micro SD card formatted FAT/FAT32
  • Make sure you name the file as gromipd3.hex and it resides in the root
  • Disconnect the GROM box from white harness
  • Insert micro SD into the slot with pins facing down
  • Attach the GROM box to the white harness
  • The led on circuit board should blink 1-2 seconds and then become solid or go off
  • Turn on ignition and switch over to GROM (SAT/CD changer) !

    • It is normal when the other end of AUX cable is _not_ connected to anything. Once iPod or MP3 player is connected there will be no noise or whine. If noise is still present after the audio source is connected then contact Technical support.

    Bluetooth

    1. Please make sure the latest firmware installed
    2. Turn the car off. Wait 30 seconds
    3. Turn the car on. Now your phone should see the GROM-CAR device. Note that your stereo may be in any mode (FM, AM, CD, SAT etc)
    4. Also note that GROM-CAR will be discoverable 3 minutes and if you do not pair the phone you have to repeat items 2-3 again
    5. Follow your phone manual and pair it with GROM-CAR
    6. Now the pairing is done and after each ignition start your phone will automatically connect to GROM-CAR !

    BTD module may go into corrupt mode. Do the following sequence:
    1. Enable mode switching state (GROM-FM-GROM)
    2. Immediatelly press SCAN button few times
    3. There should be tw0 voice beeps confirming full reset
    4. You should be able to select and connect to GROM-CAR now

    The GROM Bluetooth is capable of pairing up to only 2 devices at a time. It can only connect to one Paired device at a time. It will auto connect to the phone that is nearby when the vehicle is started.

    If you have newer smartphone, you should be able to select which paired device will handle phone calls and which will handle music streaming. This is all typically done from the phone Bluetooth settings, and available in iPhone and Android phones.

    After first turning on stereo/GROM please give the GROM 10-15 seconds to fully sync with bluetooth before hitting play on device.

    Make sure that the Bluetooth volume is turned on and all the way up.