Important Installation Notes:
If you have a basic stereo that does not have a CD changer - you will need to add optical cable (POF) to your cart.
If your stereo has CD changer, the GROM adapter will use the existing cable to connect to the stereo. Therefore the POF cable is not needed.
GROM-MST3 is the simple way to integrate USB/Bluetooth/Smartphone/AUX-In to your factory car stereo.
GROM-MST3 is a full edition of GROM adapter for MOST stereos and has two MiniDin ports for AUX-In, Bluetooth, Smartphone, iPod/iPhone connectivity (the add-ons must be purchased separately).
Please note that the USB port does NOT support iPod. You will need special iPod cable for direct ipod connectivity (track/playlist control).

USB Connection: GROM-MST3 car stereo adapter connects your USB 2.0 device such as flash drive, external hard drive or mass storage device to the stock stereo in your car. With GROM-MST3 you can listen to your digital music library and control the playback through your car stereo controls.

Bluetooth: Use your phone in the car hands free (HFP), stream your MP3 music from your phone to the factory stereo via Bluetooth Audio playback (A2DP), control your MP3 music with the car stereo or steering wheel controls via Bluetooth wireless audio control (AVRCP) with the GROM Bluetooth Dongle

AUX Input: Aux connection (for any additional audio source such as DVD, MP3 player, XM and more) plus 5V charging via AUX-In 3.5mm and 5V USB charging cable

Samsung Galaxy S and S II play and charge: If you have a Samsung Galaxy S or S II you can now play and charge it in the car using GROM SG1 cable for Galaxy. The cable has MiniDin on one side and MicroUSB on the other side. The cable is compatible with GROM-AUX and sold separately here >>

Operation of USB is simple:

• Transfer your MP3/WMA/iTunes (AAC) files to USB stick/disk/drive
• Connect GROM-MST3 car kit to your car stereo via CD changer port
• Connect USB male to female cable to GROM
• Plug-in USB disk / stick / drive into GROM

Now your stereo:

• Converted USB disk into virtual CD changer
• Plays MP3 / WMA / iTunes (AAC) files
• Browse your music files via car stereo buttons (check Operation Manual)
• Navigates through directories and map them to the disc buttons on your car stereo or steering wheel controls
• Plays higher than CD quality (18 bits) sound directly to your car stereo
• Provides additional AUX input and 5V charge via 3.5mm and USB cable (sold separately -check above)
• Provides charge and control for the iPod/iPhone (cable sold separately - check above)
• Provides Bluetooth hands free and wireless music playback from your mobile phone with the additional GROM Bluetooth Dongle

Main characteristics:

• Built-in high quality (18 bits,low noise) MP3 / WMA Decoder
• Supports USB Stick / flash drive / mass storage device
• FAT 16/32 system supported
• Higher than CD quality sound of your MP3 files with level-matching technology
• Full control over the music via steering wheel or car stereo controls
• Maps discs to root folders
• Shuffle, scan, repeat through your MP3/WMA files
• Additional audio MiniDin to 3.5mm cableto connect any MP3/Audio player
• Bluetooth handsfree and wireless music playback from your mobile phone or iPhone via GROM Bluetooth Dongle
• Playlist positions are preserved for several USB sticks
• For more information on folders, formats, operation and limits- read FAQ
• Firmware upgradeable, universal interface fits many car makes

Product Images:

Usage video:



Install Video:

Volvo XC90 with High Performance or Premium sound systems are only supported stereos, with 6CD unit + amplifier + tuner. Volvo XC90 with Basic Sound Stereo, Single CD, all in one unit is not supported yet.
Factory CD will have to be disabled to use the GROM-MST3.

Important: In some case if device is recognized and work properly but only for few seconds you will need to visit your dealer and apply MOST Security OFF patch. This patch can be removed by the authorized dealer only. This patch will allow third party integration devices to work properly with your factory stereo. Currently there is no workaround been found besides visiting the dealer.

- GROM-MOST Multimedia Box
- Optical harness
- USB Type A Male / Type A Female 6FT cable
- 2GB USB Flash Drive
- Operation manual
Optional Add-Ons (sold separately):
- GROM Bluetooth Dongle for hands free calling and wilreless playback
- iPod cable for iPod control and charge
- AUX 3.5mm cable and 5V USB charger for any MP3 player, mobile phone, XM, etc.
- MicroUSB cable for Samsung Galaxy S, SII play and charge
- Optical harness (POF) for the stereos that do not have CD changer

- 30 days money back guarantee
- 1 yr replacement warranty

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