2005 Kenwood KDC wiring question.

[family affair]

Im attempting to add a Bluetooth receiver to my old radio. The KDC wiring diagram shows:
- Red is ignition
- Yellow is power
There is a second plug that has a blue and white wire that is labeled Grady White, a black, and a red. I'm thinking this has something to do with the wired remote, but I'm not certain.
I need power to the Bluetooth receiver. Before I looked at the diagram, I was going to tap into the red, but now I'm thinking the yellow. Anyone have experience with this type of wiring?

 

[Hookup1]

This is for a different stereo but they all use the same color codes. When you make the connection do it on the radio harness side (not the boat harness side).

If you do decide to replace the stereo unit at some point save the radio side harness and use it to adapt to the new stereo harness (for example a Fusion unit). This way you have a nice clean wiring installation.

 

[family affair]

Thanks Hookup.
Looks like the blue/white wire is for the remote as I had suspected.
I get what you are saying on the wire taps.
So the question still is, do I tap the red wire or the yellow? Based on the wiring diagram yellow would make the most sense, but considering there is already a tap on the red for the remote, I'm thinking that is the way to go.
Also, any advice on how to combine these tiny wires reliably while avoiding corrosion issues is welcome.

 

[Ky Grady]

From my days of messing with audio. The yellow wire is a constant power for the memory presets. Even with battery switch off, it continues to pull juice, and in time, can run your battery down. I have my radio on red and black only. When battery switch is off, no drain on my battery.

 

[family affair]

From my days of messing with audio. The yellow wire is a constant power for the memory presets. Even with battery switch off, it continues to pull juice, and in time, can run your battery down. I have my radio on red and black only. When battery switch is off, no drain on my battery.

Thanks. That's what I suspected. I don't think the yellow is being used. I think the red is only energized when the batteries are turned on. I suppose I could grab my meter and check now that I know what the blue/white wire is.

 

[Fishtales]

Curious, what does a bluetooth receiver cost and why add it to a 20-year-old radio? My factory 2006 GW Kenwood was inside my cabin and when it stopped working I took it apart. What a mess inside from corrosion. the Kenwood is not a marine grade product at all. I went with a new Fusion head unit with helm remote, it wired in intuitively/fast and re-installed in the factory hole. I then changed the 4' and 6" speakers in the cabin and cockpit with Fusions after inspecting the Kenwoods and finding them dry and brittle. Took it a bit further adding a 2 channel Fusion amp and (2) more 6" Fusion speakers in the cockpit. If it dies in the future, consider the Fusion. You won't be disappointed.

 

[family affair]

Why?
I almost never use the radio; the receiver was $16 - if it works; I don't have the time or interest to change out the entire audio system ( see point 1); my boat and radio spent most of its life indoors, so no corrosion. Juice ain't worth the squeeze for me. I'd be happier if it didn't have a radio at all, but this is the path of least resistance with a possible bonus at the end if it works.

 

[Fishtales]

Thanks..

 

[Hookup1]

This is for a different stereo but they all use the same color codes. When you make the connection do it on the radio harness side (not the boat harness side).

If you do decide to replace the stereo unit at some point save the radio side harness and use it to adapt to the new stereo harness (for example a Fusion unit). This way you have a nice clean wiring installation.
View attachment 36557

The blue wire is a remote turn on - raise your car antenna, power your external amp on.
The yellow wire is power to the unit but the unit isn't really turned on. It's always on so it powers memory circuits too.
The red ignition wire turns the unit on and uses power from the yellow wire to run the unit.
Black is ground.
Orange/white is dash illumination which you probably won't use.

Simple tap connectors are ok with a bluetooth device since it draws little current.

 

[family affair]

It's alive! Brought the old KDC-225MR into the 2020s for $17.
Works great.



Turns out the yellow is actually continuously providing power and the red only has power with the battery switch on.

 

[Hookup1]

LView attachment 36589
Turns out the yellow is actually continuously providing power and the red only has power with the battery switch on.
[/QUOTE]
Correct. I have another boat that the radio is setup like a car. You have to turn ignition switch to acc or run to turn the radio on. Only took me a 1/2 day to figure that on out!

 

[family affair]

LView attachment 36589
Turns out the yellow is actually continuously providing power and the red only has power with the battery switch on.

Correct. I have another boat that the radio is setup like a car. You have to turn ignition switch to acc or run to turn the radio on. Only took me a 1/2 day to figure that on out!
[/QUOTE]
I'm shocked by this. Granted it probably draws milliamps, but it is a draw. I also noticed the radio goes to sleep a while after the battery switch is turned on. My guess is this is the only real difference between the car receiver and the boat version. I've always struggled to understand how to wake this damn thing up from sleep mode. Despite all the buttons, a switch labeled "on" wasn't in the cards, just "off."

 

[seasick]

Correct. I have another boat that the radio is setup like a car. You have to turn ignition switch to acc or run to turn the radio on. Only took me a 1/2 day to figure that on out!

I'm shocked by this. Granted it probably draws milliamps, but it is a draw. I also noticed the radio goes to sleep a while after the battery switch is turned on. My guess is this is the only real difference between the car receiver and the boat version. I've always struggled to understand how to wake this damn thing up from sleep mode. Despite all the buttons, a switch labeled "on" wasn't in the cards, just "off."
[/QUOTE]

The yellow lead for the marine stereo is a feed to keep it's memory and sometimes settings when turned off. The red wire is the switched power feed. Sometimes the yellow lead will be spliced into the red. In that case the stereo works when the power is turned on but your memorized station info may be lost. If your battery is not recharged, eventually your battery will run down.
In modern automobiles, there is a parasitic current draw when the car is 'shut' off. The amount of the draw can start fairly high but will reduce over time.
There are several systems that have parasitic current drain. In addition to the entertainment system, your security/immobilizer systems dram some standby amperage as will your environmental and comfort systems. There can be a several other modules that need some power all the time.

 

[family affair]

I'm shocked by this. Granted it probably draws milliamps, but it is a draw. I also noticed the radio goes to sleep a while after the battery switch is turned on. My guess is this is the only real difference between the car receiver and the boat version. I've always struggled to understand how to wake this damn thing up from sleep mode. Despite all the buttons, a switch labeled "on" wasn't in the cards, just "off."

The yellow lead for the marine stereo is a feed to keep it's memory and sometimes settings when turned off. The red wire is the switched power feed. Sometimes the yellow lead will be spliced into the red. In that case the stereo works when the power is turned on but your memorized station info may be lost. If your battery is not recharged, eventually your battery will run down.
In modern automobiles, there is a parasitic current draw when the car is 'shut' off. The amount of the draw can start fairly high but will reduce over time.
There are several systems that have parasitic current drain. In addition to the entertainment system, your security/immobilizer systems dram some standby amperage as will your environmental and comfort systems. There can be a several other modules that need some power all the time.
[/QUOTE]
That's why my truck is always connected to a smart charger/ maintainer.
I would have thought this would not be happening on boats since they often sit for long periods without use. Looks like I'm wrong.

 

[Hookup1]

I own a self storage facility and cars are stored off island over the winter (flooding). All the fancy cars draw power from the battery all the time. If these cars go dead it's nearly impossible to get into them to access the battery. Ferrari has a power/battery charger connector near the rear license plate. Not sure what Mercedes does. I have helped a few customers put solar panels on the roof of the building to charge their cars. We don't have power in the units.

Most boat manufacturers use automotive radio units. There will always be a small drain on the battery from the yellow wire.

Also the USB3 and passive phone chargers are a drain on your battery unless you tie them to a switch.