Looking for Key-on Power to Tap

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Detroit Iron

Detroit Iron

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I'm working on my '67 Dart. I have some accessories to hook up that I would like key on power for. My question is where's the best place to get power. I don't like those fuse box taps. Each of these devices I'm hooking up (stereo, seat heater) have their own fuse, so I'd rather splice into a wire, but which one? Thanks for the input.
 
The fuse panel/ ignition switch is already overloaded. I would find (do you want?) "run" only or accessory?-would find a way and use that to KEY A RELAY if you are adding much of anything for accessories

Do you have a service manual? Go over to MyMopar.com and download one for free

There are only so many "spots."

The key has an ACC (accessory) output which feeds the large "acc" buss in the fuse panel. The key has "IGN 1" which is hot ONLY in run. THAT IS NOT FUSED. It operates the gauges and warning lamps, such as oil, and goes out into the engine bay to power the VR and ignition. I WOULD NOT put ANY MORE load on that except for a relay coil

We need more specific info about what "whut all" you are going to hook up
 

Detroit Iron said:
I'm connecting a stereo which has minimal load, and a seat heater which does have a relay
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The point is you need to power the seat heater (sorry, but really?) needs a separate power source from the cars stock wiring.

Go to mymopar.com free factory service manual and wiring diagrams, or classiccarwiring.com for a full color wiring diagram (best 25.00 I ever spent)

And study the wiring.

What 67dart273 is saying, is feed the power from a new power buss fed from the Alternator output. Then tap that to feed your seat warmer. The trigger for the relay can come from same place the radio power feed currently is.

When you say stereo how many watts is it?

The stock is 2 watts so it is a relatively low power consumption device, but a modern radio capable of 25 ,50 or 100W can draw much more.
 
Detroit Iron said:
I'm connecting a stereo which has minimal load, and a seat heater which does have a relay.
Click to expand...
How many watts is the stereo PA?

A SEAT HEATER?? REALLY??

You need to investigate the ammeter bypass and whether the wiring now in place is in good shape. Most guys use a breakered/ fused large wire direct from the battery to the alternator output stud BUT YOU STILL need to make certain and check or repair the bulkhead connector leads for the ammeter

Read this article for the why


In the early 70's, stationed at NAS Miramar, ("Fightertown USA,", "Top Gun") and yeh I AM OLD I had a 70 440-6 Roadrunner. The ammeter mounting and the bulkhead connector gave me problems BACK THEN. Of course there was no internet. I had to figure it out myself. By the way, back then, I had owned a 69 383 4 speed RR and then the 440, also a 4 speed/ Dana. I HAD SERVICE MANUALS FOR THEM BOTH.
 
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He said he was using a relay for the seat heater, what’s the problem? Most relays I’ve ever used are direct from battery to a CB then the fixture. The switch/trigger for relay can’t use that much power?

To the OP, a service manual will help you a lot here in determining a good spot to take switched ignition on power from…. You can sometimes find them online.
 
4mulas said:
He said he was using a relay for the seat heater, what’s the problem? Most relays I’ve ever used are direct from battery to a CB then the fixture. The switch/trigger for relay can’t use that much power?
Click to expand...
What I've highlighted in bold is exactly the problem.

Automotive ammeters were set up to show current charging and discharging from the battery.
This was possible because the battery leg was seperate from everything else.
Any equipment added onto the battery positive or the any part of that line (up to and including the R connector on the ammeter) messes up the the ammeter reading. It also puts a load onto those connections and the fusible link. That load is in addition to any charging happening at the same time.

(the mad folks don't describe this and therefore mess up their 'solution'.)
Diagram in this post

Chrysler added switched accessories onto the switched accessories buss with a jumper in the fusebox.
www.forabodiesonly.com

Rallye cluster gauge issues - 67 Barracuda

I imagine this topic has been covered many times before, and I suspect I already know where to start looking for my problem, but am looking for some shared wisdom. I did some searching of older threads and found several related posts, but nothing that fits my situation exactly. I apologize in...
www.forabodiesonly.com www.forabodiesonly.com
 
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Mattax said:
What I've highlighted in bold is exactly the problem.

Automotive ammeters were set up to show current charging and discharging from the battery.
This was possible because the battery leg was seperate from everything else.
Any equipment added onto the battery positive or the any part of that line (up to and including the R connector on the ammeter) messes up the the ammeter reading. It also puts a load onto those connections and the fusible link. That load is in addition to any charging happening at the same time.

(the mad folks don't describe this and therefore mess up their 'solution'.)
Diagram in this post

Chrysler added switched accessories onto the switched accessories buss with a jumper in the fusebox.
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Click to expand...
This is the way to go. I tapped onto the back of the flag for accessories. Thank you for the input.
 
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