Alpine W505 power connection question

[PorknBeanz]

I’m installing an Alpine W505 and having some trouble. I bought the SOS stereo adapter to make things easier. From the Alpine manual, it looks like the head unit only needs three wires to power up: The yellow wire which is unswitched 12V+, the red wire which is switched 12V+, and the black ground wire.

My unit doesn’t power up. I’ve confirmed that the red 12V is + and that it turns off and on with the ignition key when connected to the black wire or another ground. The yellow wire which should be 12V+ unswitched seems to stay at 1.5V+ when the key is switched on and 0.6V+ when the key is off. I found the same readings on the car side of the connector and on the radio side of the SOS connector. When I plug in the OEM radio, it works fine.

Another question is that the SOS connector packaging lists a blue/white remote turn on (12V+) but my connector doesn’t have this wire. Last question, I noticed that the radio has a security in pin and a security out pin. Do I need to do anything with these? Thanks.

 

[Veleno]

If I'm not mistaken, the blue/white is for remote turn on for the amplifier.

I'm not sure about the security on the player though.

Did you purchase your w505 from an authorized dealer should you need to return it for repair? I'm guessing it should power up/turn on when you connect the 3 cables (red, yellow, black), but maybe the security thingy has something to do with it, IDK. What does the manual say about the security in/out pin?

Try to wire it up directly without the SOS harness to see if you get the same results. Simply trace the 3 wires (red, yellow, black) on the SOS harness to the OEM harness, then connect the player wire harness directly to those on the OEM harness. If it turns on then you found your problem. If not then it might be the player itself.

Let us know how it turns out.

 

[Malibu Rapper]

My unit doesn’t power up. I’ve confirmed that the red 12V is + and that it turns off and on with the ignition key when connected to the black wire or another ground. The yellow wire which should be 12V+ unswitched seems to stay at 1.5V+ when the key is switched on and 0.6V+ when the key is off. I found the same readings on the car side of the connector and on the radio side of the SOS connector. When I plug in the OEM radio, it works fine.

This is very strange. If the yellow wire is reading 1.5v and .6v, your radio should be losing its memory. Is that the case when you turn the car off?

As far as powering on your alpine radio, did you try grounding elsewhere? What you can try doing is connect both the red and yellow wire from the alpine to the red wire on the harness. Don't change your ground yet. If that doesn't work, try connecting the ground wire to the bolt on the bar underneath the radio. This should get the unit to power on.

It's rare that units don't power on from the factory. Check the fuse on the Alpine harness, too.

Another question is that the SOS connector packaging lists a blue/white remote turn on (12V+) but my connector doesn’t have this wire. Last question, I noticed that the radio has a security in pin and a security out pin. Do I need to do anything with these? Thanks.

This blue/white wire is for the other SOS harness which allows you to keep your OEM head unit. It is the power antenna wire/amp turn on wire for the OEM head unit. Do not worry about this since you are installing an aftermarket head unit.

 

[PorknBeanz]

Thanks for the tips. I finally found the answer after looking at the NSX schematic. The yellow unswitched 12V+ comes from the battery, through the clock fuse, through the clock, and then to the stereo. I must have shorted out the wire because the clock fuse (under the front hood) was blown. I replaced it and the unit powers up fine.