TK-7180 power on with ignition

[Colton25]

Hello all, i'm about to install a 7180 in my car and i'm wanting it to come on with the turn of the ignition. Can anyone tell me how i would wire this into the fuse box?

 

[mmckenna]

There should be a yellow lead coming out of the radio with a bullet type connector on the end, likely capped off with a clear cover. This is the ignition sense lead.

You can purchase an "official" Kenwood KCT-46 cable, which is basically a piece of yellow wire with a bullet connector to match the radio and a fuse holder and a 3 amp fuse. It's cheaper to make your own, though.

You'll need to locate an ignition switched power source to tap into. This will vary depending on your vehicle. Often, people will use fuse taps to do this, but they can cause issues if they are the type that jam in around the existing fuses. I've always found an unused accessory source to tap into, actually tying into a wire to prevent fuse box issues. On my old truck I tapped into an unused sun roof power lead (truck didn't have a sun roof, so the power lead was just taped off in the "A" pillar.) Figuring out exactly what you need to use for your specific vehicle will either take some work with a multimeter, or searching the internet for info on your vehicle.

Once you have that done, you need to go into the radio with the programming software (KPG-89) and turn the function on. There is a couple of options:
Ignition sense only - turns radio on/off with ignition.
Ignition sense and power switch - radio turns on/off with ignition, or with power switch.

The other option you can set is "timed power-off" This is where you can tell the radio to turn on with the ignition, and to turn off a set amount of time after the ignition turns off. This is a hand feature if you want to still use the radio after the ignition is turned off. If you start your ignition before it times out, it resets to normal.

 

[mmckenna]

This can be a useful source of information: Car Alarm, Car Stereo, Mobile Video, and Cruise Control Info for Installers
Look up your specific vehicle and see if someone has posted info on where to find a suitable switched ignition feed.

 

[Colton25]

There should be a yellow lead coming out of the radio with a bullet type connector on the end, likely capped off with a clear cover. This is the ignition sense lead.

You can purchase an "official" Kenwood KCT-46 cable, which is basically a piece of yellow wire with a bullet connector to match the radio and a fuse holder and a 3 amp fuse. It's cheaper to make your own, though.

You'll need to locate an ignition switched power source to tap into. This will vary depending on your vehicle. Often, people will use fuse taps to do this, but they can cause issues if they are the type that jam in around the existing fuses. I've always found an unused accessory source to tap into, actually tying into a wire to prevent fuse box issues. On my old truck I tapped into an unused sun roof power lead (truck didn't have a sun roof, so the power lead was just taped off in the "A" pillar.) Figuring out exactly what you need to use for your specific vehicle will either take some work with a multimeter, or searching the internet for info on your vehicle.

Once you have that done, you need to go into the radio with the programming software (KPG-89) and turn the function on. There is a couple of options:
Ignition sense only - turns radio on/off with ignition.
Ignition sense and power switch - radio turns on/off with ignition, or with power switch.

The other option you can set is "timed power-off" This is where you can tell the radio to turn on with the ignition, and to turn off a set amount of time after the ignition turns off. This is a hand feature if you want to still use the radio after the ignition is turned off. If you start your ignition before it times out, it resets to normal.

I had noticed the yellow wire but wasn't sure what it was used for. So if i utilized the yellow wire i wouldn't need to use the regular red power wire? I have found a fuse which is the HVAC W/ignition it is currently in use but i pushed the red wire in next to the fuse and the radio seemed to turn on fine with the ignition on. I'm assuming the yellow wire just gives you the ignition options when you are programming?

 

[mmckenna]

No, you still need to supply power to the radio using the red and black leads. The yellow wire is only for the ignition control, it will not power the radio.

Your red and black power lead should come direct from the battery, as this will give you a clean/reliable source of power with sufficient current capacity for the radio to perform properly. Tapping into other circuits for the radio power can introduce all kinds of noise into your signal, and it's entirely possible that you will blow a fuse, or worse, if you attempt to power it off an existing circuit.

The yellow lead goes to an ignition switched source. When it senses 12 volts DC, it will perform the function that has been programmed.

So, you need three wires to do what you want. The black and red power leads need to go to the battery, with fuses within a few inches of the battery to protect the rest of the wiring. Don't skip this part.
The yellow wire needs to be connected to an ignition switched source, and fused close to that tap in point. Again, don't rely on other fuses that may or may not be there.

 

[Colton25]

No, you still need to supply power to the radio using the red and black leads. The yellow wire is only for the ignition control, it will not power the radio.

Your red and black power lead should come direct from the battery, as this will give you a clean/reliable source of power with sufficient current capacity for the radio to perform properly. Tapping into other circuits for the radio power can introduce all kinds of noise into your signal, and it's entirely possible that you will blow a fuse, or worse, if you attempt to power it off an existing circuit.

The yellow lead goes to an ignition switched source. When it senses 12 volts DC, it will perform the function that has been programmed.

So, you need three wires to do what you want. The black and red power leads need to go to the battery, with fuses within a few inches of the battery to protect the rest of the wiring. Don't skip this part.
The yellow wire needs to be connected to an ignition switched source, and fused close to that tap in point. Again, don't rely on other fuses that may or may not be there.

So would it be a good idea to tap the yellow wire into that HVAC W/ ignition fuse i was talking about?

 

[mmckenna]

So would it be a good idea to tap the yellow wire into that HVAC W/ ignition fuse i was talking about?

That should work, however any time you tie into power, you are introducing a path that noise can get into your radio. HVAC systems are notorious for having RF noisy blower motors. I'd suggest trying to find something a bit more quite, something without a motor.

These types of fuse taps are a better choice, as they do not involve stuffing anything extra into the fuse socket:
ATC ATO Add A Circuit Fuse Holder Tap - The Repair Connector Store
(note, this is for an ATO fuse, you need to figure out exactly what type of fuses your vehicle uses and purchase accordingly)

The fuse taps that stick a piece of metal down in with the fuse tab have a bad habit of forcing the contacts apart, which can lead to intermittent failures down the road.

 

[Colton25]

That should work, however any time you tie into power, you are introducing a path that noise can get into your radio. HVAC systems are notorious for having RF noisy blower motors. I'd suggest trying to find something a bit more quite, something without a motor.

These types of fuse taps are a better choice, as they do not involve stuffing anything extra into the fuse socket:
ATC ATO Add A Circuit Fuse Holder Tap - The Repair Connector Store
(note, this is for an ATO fuse, you need to figure out exactly what type of fuses your vehicle uses and purchase accordingly)

The fuse taps that stick a piece of metal down in with the fuse tab have a bad habit of forcing the contacts apart, which can lead to intermittent failures down the road.

Ok got it, what size fuse should i use for the yellow wire?

 

[mmckenna]

Kenwood ships the KCT-46 with a 3 amp fuse. Using the same would be a good idea. Likely it draws very little current.

I use this set up on my work truck. I have a Kenwood NX-700 VHF and an NX-900 800MHz radio in there, same body radio as the TK-7180, same ignition switched power set up. Using the ignition switch feature with the power off delay works well. I have them set to 2 hours, which works well, and keeps the radios from running down the battery.

 

[Colton25]

Kenwood ships the KCT-46 with a 3 amp fuse. Using the same would be a good idea. Likely it draws very little current.

I use this set up on my work truck. I have a Kenwood NX-700 VHF and an NX-900 800MHz radio in there, same body radio as the TK-7180, same ignition switched power set up. Using the ignition switch feature with the power off delay works well. I have them set to 2 hours, which works well, and keeps the radios from running down the battery.

Got it. Hey thanks for all the help and info, really needed it!!

 

[mmckenna]

No problem. I enjoy this stuff, glad I could help.

 

[hitechRadio]

Just to add for other people reading about ignition sense.
If the radio is on a trunking system. The Red and Black should be powered all the time and yellow to ignition. The radio will not deregister if you hook Red to switched power.

The same applies to most all trunking radio's, Including Motorola radio's.

If the radio is powered on all the time and you use the power button to turn the radio on and off, you do not have to worry about ignition sense wire.

A lot depends on programing with some models/manufactures also.

 

[ramal121]

Just to add for other people reading about ignition sense.
If the radio is on a trunking system. The Red and Black should be powered all the time and yellow to ignition. The radio will not deregister if you hook Red to switched power.

The same applies to most all trunking radio's, Including Motorola radio's.

If the radio is powered on all the time and you use the power button to turn the radio on and off, you do not have to worry about ignition sense wire.

A lot depends on programing with some models/manufactures also.

Well this thread is for a TK-7180 which only supports LTR trunking. Since there is no affiliation required for LTR, killing the power has no effect. If you have an NX with type D trunking, then yes your words are very wise.

But all in all, if a trunking radio suddenly disappears, there is no harm to the subscriber radio. The trunking controller may be confused for a time but will eventually figure it out. But as you mentioned this is not the polite way to do things.

 

[hitechRadio]

Well this thread is for a TK-7180 which only supports LTR trunking. Since there is no affiliation required for LTR, killing the power has no effect. If you have an NX with type D trunking, then yes your words are very wise.

But all in all, if a trunking radio suddenly disappears, there is no harm to the subscriber radio. The trunking controller may be confused for a time but will eventually figure it out. But as you mentioned this is not the polite way to do things.

Yes I understand, but unlike some people I did a search instead of starting a new thread looking for if the yellow cable needed to be programmed to work correctly.
We have several NX series radios from another agency to install in supervisor cars. And thought I would mention for others, if they came across this thread.

It seems our NX radio's the agency did not program the yellow wire, so there hundreds of radio's are not deregistering, ( console switch to turn everything off in the car) its there system though not mine. I will bring it to there attention, as they are having a few unexplained issues with there 7 site NXDN system.

Not sure about NXDN D-trunk as you mentioned, thought D was more like LTR, which I would not think would require deregistration. This customer is using NXDN C-Trunking centralized. But I am no NXDN expert.

I agree though that ultimately it is not a huge deal to not deregister, unless it is a multisite site system as this system is. Needlessly dragging TG to sites using up limited resources.

Being our agency uses a P25 7.X multisite system, it is important to have the radio's deregister, as we have mixed number of channels at each site. Although our system is setup to check radio/s to see if the are still on the system, Control Stations for example, that will sit turned on not used for extended times. I am not sure how they set up this feature on there NXDN C system though.

 

[mmckenna]

I've got a single site NexEdge system and it isn't an issue for us.

It's no different than a radio going out of range of the system before logging off. It just disappears.

I do believe there is an option in the trunking system where you can force it to wipe all the registrations at a set time every day. This would clear out any issues and radios would re-register.

I don't see this as being a big deal, and we don't know the OP is even using trunking...

 

[hitechRadio]

Yes , I don't see were it would be a big problem in a single site system NXDN C. Multisite it can be however.

I did not mean to get off topic, but as I mentioned. I came across this thread looking to see if the yellow wire needed to be programed to work correctly. You had answered my question on that in post #2, and it indeed needed programed. We do not have the software as of yet for these radio's.

I realize now the OP may not be using trunking, I am not up on the Kenwood models. I just wanted add the part on ignition sense for radio's on a trunked system (especially NXDN C) just incase someone came across this thread (as I did) looking for use of the yellow wire.

Thanks