Hey everyone my stock nakamachi radio in my 94 sc400 wasnt getting any power, so i figured it was the head unit. ordered a new single din radio and adapter and harness, but it still wasnt working. i checked both the fuses (in engine bay and understeering wheel) everything is connected in the trunk, and everything else in the car works besides the radio. the previous owner ghetto wired some aftermarket speakers and left the wires for them hanging all around after he removed the speakers.
so the only thing i can think of so far is maybe its a bad ground. if it is, i have no idea where the wire is grounded to. i researched for 2 hours and couldnt come up with anything. if anyone has a solution or knows where the ground is grounded please chime in. any help is appreciated. ive been stuck on this for a couple days now and im sick of driving around without a headunit. thanks!

 

Volt meter or test light, confirm your 12v and acc wire has power?

 

Dude ground is sooooooooo easy to figure out. On the wire harness for the head unit find out which wire is ground...... I bet its the black wire. Now take a voltage meter and put it on Ohm test. Put one lead on ground wire (make sure it's touching wire) and the other lead on a good body ground, like a bare screw bolted into the car's metal body. If you get a open lead read out then your ground is bad, if you get a small resistance amount then you are probably good. Screw tracing the ground out to factory spot, if the only issue is head unit not turning on then get a sheet metal screw and screw the ground cable into the body to make a new ground.

 

The left bottom screw of the metal frame that holds the radio and a/c unit is a ground point. Try using that instead of the ground from the harness. Using the harness ground sometimes works, other times it doesnt. More info here

https://www.clublexus.com/forums/lex...b-working.html

 

It sounds to me like the amp is no good. I would check that if the grounds are ok.