Audio Radio will not turn on.

[stock333]

Installing new Audio radio. I have 13 to 14volts coming out of new harness. but radio will not go on. If i hook up radio directly to battery it turns on. Any idea why radio is not turning on. bought 1 and the this happened so i thought it was the radio so i bought a new one and its the same problem

Thanks

Mark

[mmwjr]

Have you verified the negative wire is good?

[stock333]

How to do that

[stock333]

If i use a multi meter with the blace and red i get 13 volts.. if i do the black and yellow i also get 13 volts

[donald]

Red + should be power for the radio, yellow is for backup so that the radio does not lose its memory, usually not used on a boat as the MBSS kills all power to the boat.
Don

[stock333]

sorry but what is the MBSS

[mmwjr]

Originally Posted by mmwjr

Have you verified the negative wire is good?

Using an ohm meter and a long piece of wire connect one end of the wire to the black in the harness then the other end to one lead of the ohm meter. Now touch the other meter lead to the battery negative post and you should get < 5 ohms.

[mmwjr]

Originally Posted by donald

Red + should be power for the radio, yellow is for backup so that the radio does not lose its memory, usually not used on a boat as the MBSS kills all power to the boat.
Don

Be careful as on newer boats they switched and use yellow as negative 12VDC since folks were mixing it up with hot 110VAC.

[donald]

Master Battery Selector Switch (MBSS).
Don