628UA - Hi-Fi System BOSS - Free user manual and instructions

Product Type	AM/FM Digital Media Receiver (MP3-Compatible)
Brand	BOSS Audio Systems
Model	628UA
Power Supply	DC 12V (negative ground)
Maximum Power Output	50W x 4 channels
Speaker Impedance	4 – 8 Ohms
Unit Dimensions (W x H x D)	7.0 x 2.0 x 3.8 inches (178 x 51 x 97 mm)
Weight	1.54 lb (0.7 kg)
Fuse	15A
Radio Frequency – FM (USA)	87.5 – 107.9 MHz (200 kHz step)
Radio Frequency – FM (Europe)	87.5 – 108.0 MHz (50 kHz step)
Radio Frequency – AM (USA)	530 – 1710 kHz (10 kHz step)
Radio Frequency – AM (Europe)	522 – 1620 kHz (9 kHz step)
Usable Audio Formats	MP3, WMA
Pre-amp Outputs	Front and Rear RCA (2V nominal)
Frequency Response	20 Hz – 20 kHz
Signal-to-Noise Ratio	60 dB
Media Sources	Radio (AM/FM), USB, SD Card, AUX In
Preset Memory	30 stations (6 per band: FM1, FM2, FM3, AM1, AM2)
Equalizer Modes	FLAT, POP, ROCK, CLASS
Display	LCD with backlight
Detachable Front Panel	Yes, with release button
Remote Control	Includes (CR2032 battery)
Safety Features	Lithium battery cell warnings; fuse protection; do not self-repair

Frequently Asked Questions - 628UA BOSS

How do I set the clock on the BOSS 628UA?

Press and hold the CLK button for more than 2 seconds until the time flashes. Rotate the volume knob to adjust hours, press CLK to switch to minutes, then rotate to adjust minutes. Press CLK again to confirm.

What should I do if the unit has no power or sound?

Check that the car's ignition is turned to ACC or ON. Ensure all wiring connections are correct and the 15A fuse is not blown. Also verify the volume is not muted or set too low.

How can I reset the BOSS 628UA to factory defaults?

Press the MUTE button to flip down the front panel, then remove the control panel. Use a sharp object to press the RESET hole. This will erase all preset stations and clock settings.

How do I insert and play music from an SD card?

Press the MUTE button to flip down the front panel, then remove it to access the SD card slot. Insert the SD card, reattach the panel, and close it. Press SRC to switch to SD mode.

Why is there static when listening to the radio?

Weak station signals cause static. Try selecting a stronger station with stronger signal strength. You can also switch between US and EU frequency steps to improve reception (press and hold VOL).

How do I store and recall preset radio stations?

Tune to the desired station, then press and hold one of the 1-6 buttons for more than 2 seconds. To recall, briefly press the preset button. The unit has 5 bands (FM1, FM2, FM3, AM1, AM2), each storing up to 6 stations.

Can I play music from a USB flash drive?

Yes, insert a USB flash drive into the USB port on the front panel. Press SRC to select USB mode. Supported audio formats are MP3 and WMA.

What are the equalizer presets available?

During USB or SD playback, press the volume knob to cycle through EQ modes: FLAT, POP, ROCK, and CLASS. In radio mode, pressing the volume knob adjusts Bass, Treble, Balance, and Fader.

How do I remove the front panel for security?

Press the MUTE button to flip down the panel, then grip the panel and pull it out. To reattach, align the panel and push it back until it clicks. Always store the panel in a safe place.

The preset stations are lost after turning off the car. What's wrong?

The yellow Power B+ wire must be connected to a constant 12V supply (battery terminal that is always live). If it is connected to a switched source, presets will be lost when the ignition is off.

USER MANUAL 628UA BOSS

Lithium Battery Cell Warnings 1
Use Cautions ....1

Installation 2

Installation Procedures 2
Installation Opening....2
Wiring Connections....3
Uninstall the Main Unit 3

Control Panel Button Locations 4

Operation 4

Power / SRC 5
Adjust Menu Options (SRC) 5
Change the Source (SRC) 5
Store/Recall Preset Stations-(1-6) 5
Play/Pause 5
Next/Previous Track 5
Fast Forward/Backward 5
Set the Clock (CLK) 5
Insert SD Card 5
Adjust Volume (VOL) 5
Switch Between US and EU-Frequency 5
Manual Tuning·(|<</->|) 5
Auto Seek Tuning (|<</>>|) 5
Change Bands (BAND) 5
Automatic Music Search (AMS) 5
Track Search 5
Track/Folder Navigation 5
Mute 6
Insert USB 6
AUX In Jack 6
Release Panel 6
Reset System (RESET) 6

Remote Control 7

Remove Insulating Sheet 7
Button Names and Locations....7

Troubleshooting 8

Specifications 9

Lithium Battery Cell Warnings

• Cell leakage may cause damage to the remote control.
• Do not throw cells into fire, as this may cause an explosion.
- Keep battery cells out of reach of children.

Use cautions

• To reduce the risk of fire, electric shock, and annoying interference, do not repair yourself. Please refer serving to qualified person.
• Some MP3/WMA files may not be playable.
- Keep lower volumes to concentrate on traffic and road conditions for safety driving.
- If users' car is under sunlight for sometime, please lower the temperature inside the car then start the player operation.
• If the battery is disconnected or discharged or changed, the preset memory will be erased and must be reprogrammed.
• Installation of unit is better at a horizontal position, or if it is at an angle, it may be not working at its best situation.
• Never use force or grip the display and the buttons tightly when removing or attaching,
- Be sure to lower the volume before switching off the unit or the ignition key.

Installation Procedures

First complete the electrical connections and then check for correctness.

Installation Opening

This unit can be installed in any dashboard. Having an opening as shown above.

Insert mounting collar into the dashboard and bend the mounting tabs out with a screwdriver.

Make sure that lock lever(※) is flush with the mounting collar (not projecting outward).

Pure technical line drawing of a mechanical component inside a transparent housing (no text or symbols)

Secure the rear of the unit.

After fixing mounting bolt and power connector, fix the rear of the unit to the car body by bubber cushion.

• Only use speakers with 4 ohms impedance.
• Do not attach the control panel to the chassis before wiring is complete.
• The maximum current of the auto antenna is 200mA.

Wiring Connections

Uninstall the Main Unit

1. Remove the metal strap from the main unit.
2. Remove the plastic trim out from the main unit.
3. Insert a bracket key into the left and right side of the main unit and draw the unit out of the mounting sleeve.

CONTROL PANEL BUTTON LOCATIONS

REMOVE PANEL

OPERATION

1. POWER/SRC

Press the POWER button to turn on the unit, and long press it again to turn off the unit.

When the unit turn on, short press POWER/SRC button to switch the unit between

RADIO,USB&CARD, AUX IN,modes (if there are USB and SD card inside the unit).

1/. If there is no USB & SD card, then it will be only radio and Aux. When the user

inserts a USB flash drive or SD Card, their respective logos will illuminate on the display.

2-7.(button 1 to 6) PRESET MEMORY BUTTONS In Radio mode

To memorize the frequency, press one of the six preset buttons(1-6) hold for more 2"S, the frequency is successfully stored.

Therefore there are FM1, FM2, FM3, AM1 & AM2, each band can store 6 stations, so total 30 stations can be stored.

To recall the preset memory station, press one of the preset buttons(1-6) plus the BND button for FM1, FM2, FM3. AM1 & AM2.

During USB or SD card mode, press '5/-10' button to go backward 10 tracks.

Press '6/+10' button to jump foward 10 tracks.

During USB or SD card mode, long press '5/-10' button to go back 1 folder.

Long press '6/+10' button to go up 1 folder. You can repeat this function depending on

the number of folders. This button will have no function if the USB or SD card has no folders.

8. CLK

Press the CLK button once to display the real time, With time appearing on the display. Press and hold CLK button for more than 2 seconds until the time flashes. You can adjust the HOUR and MINUTE by pressing the >>1 button and 1<<button respectively and press the CLK button to switch the HOUR and MINUTE.

9. SD CARD SLOT

Press the 🔊 button to flip down the front panel. Remove the front panel to gain access to the SD card slot. Insert an SD card, then attach and close the front panel. Switch to SD mode when you wish to begin SD card playback.

To remove the SD card from the unit, press the ⏚ button to flip down and remove the front panel, then push the SD card with your finger nail, the SD card will be ejected.

10. VOLUME adjustment

In the radio mode, rotate the volume knob to increase or decrease the volume level of the sound output. Press the volume knob, it will be switching the sequence as follows:

graph LR
    A["Bass"] --> B["Treble"]
    B --> C["Balance"]
    C --> D["Fader"]
    D --> E["EQ off"]
    E --> F["Loud Loc/DX Stereo Vol"]
    F --> G["Feedback Loop"]

In the USB or SD card mode, press the volume knob to enter the EQ function that the audio mode in the following order: EQ OFF → FLAT → POP → ROCK → CLASS

At the radio status, press and hold the VOL button to enter switch state of the US(USA) and EU (EUROPE) frequency, then rotate the VOL knob to select US frequency or EU frequency, after selecting US or EU frequency, the system will switch to the selected frequency 3 seconds later.

11.FF(>>|) &12.FB(|<<)

In the radio mode, long press the FF(>>1) or FB(1<<) button for more than 2 seconds, the unit will search the next or previous frequency step by step.

Short press the FF(>>1) or FB(1<<) button, the automatic search will start, it will search upward or downward for the strong signal radio station within the cuttent band. The auto searching will stop until find a station.

13.BND/AMS

In radio mode, short press the BND/AMS button repeatedly to select the one of the radio band: FM 1, FM 2, FM 3, AM1, AM2 in a cycle sequence. When you select a band, the word F1、F2、F3 for FM band, and A1、A2 for AM band will be shown on the LCD display.

Press the BND/AMS button for several seconds, the radio searches form the current frequency and the signal strength until one cycle search is finished. When the 6 strongest stations will be stored into the corresponding preset number within the current band. Short press the AMS button to scan each preset station in each band.

During USB or SD playback, short press the BND/AMS button to enter track search mode, then rotate the VOL knob to track forward or backward; if no any operation in 5 seconds, it will play the current track.

14. MUTE

Short press the MUTE button to turn MUTE ON/OFF, when it is on, the MUTE will be flash on the LCD and no sound output. When short press again it will be cancelled.

15. USB PORT

16. AUX IN JACK

17.

If you want to insert or remove the SD, reset the unit, remove the front panel from the head unit, press the 🔊 button to flip down the front panel.

18. RESET

To reset all parameters to factory default values. Press the 🔊 button to flip down the control panel form the head unit and remove the control panel, then use a subject with a sharp point end to thrush the RESET hole.

Button Names and Locations

1. Power button
2. MUTE button
3. CLK (clock) button
4. LOUD (loudness) button
5. AMS (automatic music search) button
6. PREV (previous) button
7. EQ (equalizer) button
8. SRC (source) button
9. RPT (repeat) or 3 button
10. INT (intro) or 2 button
11. LOC (local) button
12. VOL (volume) button
13. SEL (select) button
14. BAND button
15. ST (stereo) button

16. || or 1 button

17. NEXT button
18. RDM (random) or 4 button
19. • 10 or 5 button
20. • 10 or 6 button

Note: To operate remote, pull out the plastic from battery compartment at back of remote. Then point remote at unit and start.

If you suspect something is wrong immediately switch power off. Do not use the unit in abnormal condition, for example without sound, or with smoke or foul smell, can cause fire or electric shock. Immediately stop using it and call the store where you purchased it. Never try to repair the unit yourself because it is dangerous to do so.

General

No power or no sound

Car's engine switch is not on. Turn your car's key to ACC or ON.

Cable is not correctly connected. Check connection.

Fuse is burnt. Replace fuse. Check volume or mute on/off.

Radio

A lot of static in broadcast

Station or signal is too weak.

Select other stations of stronger signal level.

Preset station is reset

Battery cable is not correctly connected.

Connect the battery cable to the terminal that is always live.

USB / SD

USB or SD card is connecting but No Sound

USB or SD card connection is not good.

Take it out and insert again.

USB or SD card is damaged or no music file inside.

Change to another USB or SD card, or record music inside it.

General

Power supply Requirement : DC 12V

Maximum power output : 50W X 4CH

Speaker impedance : 4 - 8 Ohm

Unit Dimensions(WxHxD) : 7.0 X 2.0 X 3.8 inch

Weight : 1.54 Lb (0.7 kg)

Fuse : 15 A

RADIO

FM

Frequency Range USA / EUROPE: 87.5 MHz - 107.9 MHz / 87.5 MHz - 108.0MHz

Channel step: 200 KHz / 50 KHz

AM

Frequency Range USA / EUROPE: 530 KHz - 1710 KHz / 522-1620 KHz

Channel step: 10 KHz / 9 KHz

USB/Card

Usable Audio Formats ...... MP3/WMA

Pre-amp Output ...... Front and Rear

Frequency Response 20 Hz - 20 KHz

S/N Ratio 60dB

USER'S MANUAL

628UA

MP3-COMPATIBLE DIGITAL MEDIA AM/FM RECEIVER

BOSS®

AUDIO SYSTEMS

BOSS Audio Systems

3451 Lunar Court • Oxnard, CA 93030

www.bossaudio.com | 800.999.1236

tech support: www.bossaudio.com/support

CE

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