PLEASE HELP ME with car audio problem.

[dpayers1234]

Installed new JVC stereo, after old aftermarket stereo suddenly put out limited sound, (clean, but can barely hear it at max).
Had electrical checked, used ohm meter and sound generator to check speakers... still have the same low volume problem.
Am I missing a setting?

 

[Alabalcho]

At speaker connections on the car side, measure resistance between ground and each speaker terminal, and between terminals themselves. This will tell you whether you have any bad / short connections win the internal car' wiring.

 

[dpayers1234]

At speaker connections on the car side, measure resistance between ground and each speaker terminal, and between terminals themselves. This will tell you whether you have any bad / short connections win the internal car' wiring.

 

[dpayers1234]

Thank you, but i did check resistance, used a tone generator, and had the vehicle's electrical system checked. All is good.
This is the second unit with the same problem.
Am I missing a settig of some sort? Can the aftermarket interface have something to do with this issue?