Common Problems and Solution


A. No display, unit will not turn on;

Reason: There is no power supply.

Solution: 

  1. Check the wiring, both yellow and red wire should be connected to battery + (positive), black wire to battery – (negative);

  2. Measure if the battery is of proper voltage, between 12-16V DC;

  3. Check if the fuse is loose or blows; 


B. Fuse blows;

Reason: power wire were connected in reverse.

Solution: Make sure your AM/FM antenna is properly connected,  change another AM/FM antenna to test again.

  1. Change the fuse, both yellow and red wire should be connected to battery + (positive), black wire to battery – (negative);

  2. Inner circuit already burnt out (protection diode and power chip burnt), please go to technician for repair or ship back to Velex for further check and repair;


C. Radio wrecked;

Reason:  Wrong power supply (higher voltage than 12V DC).  


D. Sound distortion;

Reason: Speaker wire short circuit, or your power extension cable is too slim/thin, which makes main power supply to head unit insufficient.

Solution: Make sure your AM/FM antenna is properly connected,  change another AM/FM antenna to test again.

  1. Insulated the unused speaker wires;

  2. Replace the power extension cord, load-carrying current should be greater than 10 amperes.


E.Unit has power, but no sound;

Reason:  One or more speaker wire touching each other or touching the chassis ground;

Solution:  Insulate all bare speaker wires from each other and chassis ground;

 Reason: Speaker wire not connected;

Solution: Check connection at speakers;


F. Sound deep and low;

Reason: Speaker not matching head unit;

Solution: Change to high sensitive speakers with RMS wattage 25W-30W;


G. Unit turn on but some function missing;

Reason: Firmware loss;

Solution: Contact Velex for technical support or upgrade programming;


H. USB stick not working

Reason: USB type or Song format not supported;

Solution: Change to common brand USB stick ( max 16GB), make sure your song format are MP3 /WMA.


I. Couldn’t pick up the radio station

Reason: Antenna open circuit or weak signal;

Solution: Make sure your AM/FM antenna is properly connected,  change another AM/FM antenna to test again.


J. Bluetooth not able to pair;

Reason: Bluetooth paired to another device;

Solution: Disconnect other paired Bluetooth device and search again via your smartphone.