F355 Stereo / Wiring question.

Maybe they cut the wire upstream from the connector to tap power. Test it with a volt meter....

 

Maybe an obvious thing, but did you have the ignition turned to "accessory mode" when you tried powering up the new radio?

I presume Becker Autosound could give you the mapping of what each port/wire on the back of the radio needs (which pair is power, which is left speaker, etc). Then you need to take a meter and see if the car side of the wire loom matches up.

I'm located in the NYC area also, if you want to take a drive over I can help.

 

This should be an accurate wiring guide for a 355:

Car Radio Battery Constant 12V+ Wire: Yellow
Car Radio Accessory Switched 12V+ Wire: Red
Car Radio Ground Wire: Black
Car Radio Illumination Wire: N/A
Car Radio Dimmer Wire: Orange
Car Radio Antenna Trigger Wire: Blue

Left Front Speaker Positive Wire (+): White
Left Front Speaker Negative Wire (-): White/Black
Right Front Speaker Positive Wire (+): Gray
Right Front Speaker Negative Wire (-): Gray/Black

 

The Becker uses a European standard ISO harness for both the power and speaker connections. The speakers connection is usually brown and the power harness is usually black. On the power harness, check the red wire for switched power (via multimeter or test light) as others have said.

After this, check the ground wire (black wire) but initially you should at least get ground from the antenna connection (enough for testing but check afterward).

 

Check these wires with a meter:

Car Radio Battery Constant 12V+ Wire: Yellow
Car Radio Accessory Switched 12V+ Wire: Red
Car Radio Ground Wire: Black

If the yellow wire doesn't have +12V, check for a blown fuse somewhere. Did you turn off the battery before you started working on the wiring? Maybe it shorted when you were removing the old radio.

- Tom

 

Hmmm. That rules out fuses then. Here are the connection diagrams for the Becker and the Alpine. If the +12V and ground are connected along with the switched 12V, then the unit should at least power on.
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My factory radio has to be turned on and off. It stays on with the key out. This was the way the 99 were anyway. Kinda a pain they were not hooked to the accessory but constant power.

 

I have the same with my Becker radio, is there any solution for this?

 

I would say your radio installation was incorrectly wired. The car radio 12 vdc constant was switched with the 12 vdc key switched power. I believe the 12 vdc constant power is just to maintain memory and clock type functions. The other "hot" wire from the car harness (indicated to be red) is also 12vdc but is "switched" through the ignition switch when actuated with the key. This is to prevent the chance of leaving the radio "on" and killing your battery. Easy to fix, just pull your radio and correct wiring.

 

Thanks, I'm gonna have a look to it one of the next days.

 

I have the same issue, even when the key is out the radio is still on.

Can anyone help with this?

 

Modern car stereos have two power inputs identifiable by color specific to the U.S. Most units have an internal battery and constant power connection to the car battery via a yellow wire from the back of the radio. There is also a red wire. This wire connects to the ACC via the key. When the key is turned to ACC or first position, the radio has power. Depending on the position of the onff switch on the radio, the radio may be or or off. In your situation, the red wire is connected directly to the battery, hence constant power regardless of the key position which explain why the radio is on. Simply disconnect the red wire and reconnect it to the ACC wire. You can determine the ACC wire by testing with a D.C. Volt meter. Turn key to position one. Test and note all wires with 12v. Turn key off and note the voltage or absent thereof on those wires. The wire with zero volt is the key switched wire. That's the wire you connect the red wire from the radio to.

As mention above after market car radios in the U.S. have a color code. The three important ones are yellow, red and black. The yellow wire goes to the battery positive terminal. The red one goes to the key switch(ACC). The black one is ground.(car chassis). While the metal housing of the radio casing is "grounded", it is not intended to be used as a ground connection without the black wire properly grounded.

Note: "ground wire" in DC circuit is actually a negative wire. A return path for current flow and not the same as in AC circuit

 

If existing radio works, it implies the fises and wiring inside the car works as it should. The stereo shop determined the Becker unit works when they tested it. A logical problem is in the connection between the car and the Becker radio. Different brand uses different connection configuration. Don't assume they are interchangeable. The placing of wires within the connection housing matters. While the male and female pieces may fit physically, they may not electrically. You can actually damage the radio if the 12v wire mates to other wires not intended. The problem could simply be loose pin(s) within the connection housing. Post pictures of the wires from the back of the Becker radio. If it's a U.S. Model, the color code is etched in my head. If not, I bring out my enigma machine to decipher it.