Airflite40

I am trying to install my new stereo. I followed the wiring diagrams and head unit diagrams exactly. I turned on the car (not started) and pressed power on the radio and it just stared back at me, doing nothing. I checked the wires again, and still nothing. Then I broke out the multi-tester and checked the voltage between the constant 12v and the ground, and I got around 9V. That seemed a little low, so I rechecked the ground wire and the other connections and still nothing. Then I pulled out the radio and connected and disconnected all of the wires. I then ran two wires from the battery. I checked the voltage and it was a tad over 12v. The radio still wouldn't turn on. Does this mean the radio is bad???

jserio

Try to get us a pic as clear as possible. Check the radio fuse for ****s and giggles and then get a good strong hot wireand a good ground and test the radio. make sure you put the red and yellow together on the hot. If she lights up then the radio is more then likely good.

Airflite40

I didn't know I was supposed to put the red and yellow together to test it. Will do that tomorrow. Thanks Joe.

911Dave

Are you sure you tested the right hot wire? There are two hot connections to the radio, one constant for retaining the presets and clock (yellow), and one that's switched from the ignition circuit that provides the running power to the radio (red).

Airflite40

So, the ignition one provides the running power then? I think that's where the problem is. Thanks guys. I'll verify that when I get off of work.

911Dave

The big red wire is from the ignition switch, which causes the radio to turn on and off with the car. The new radio harness should have a red wire that this connects to. Then there's a smaller red wire which provides full-time juice to the clock and station presets. This smaller red wire connects to the yellow wire from your radio harness.

jserio

Dave, The last few radios I have dealt with had res and yellow wires. I think the yellow for contant hot and the red for ign on off hot. Could be the other way around.

911Dave

Joe, that's right. The car wiring has big red and small red, and the harness that comes with the radio has red and yellow.

jserio

Ah, I see you were talking from the car standpoint.