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Help - Radio wiring

Big_D_Snr

Freshman Member
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I feel inadequate!!!!!
If it's mechanical, problems are often visible, sometimes not, but usually there is a logical solution (but not always).
All things electrical are a wonder to me. Unless I can see a broken wire or blown fuse then I am at loss. Dave Jnr has kindly donated a Kenwood radio / cd player for fitment in the 'B'. Alas no fitting instructions. With some wood work skill I managed to over come the difficulty of fitting the unit into to the console.
Now the mystery - the wiring. I've fitted two rear speakers into the side panes and run and connected the wiring to the unit.
I have two power cables coming from the unit, these are tagged 1. Ignition, 2. Power.
If 1. goes to the ignition switch which connector is it fitted to?
Does 2. connect to the fuse box, if so which connection?
Or maybe I have got it all wrong.

Somebody somewhere please help.
 
Hi, Big D -

The wire marked "Ignition" should be connected to a post which is hot when the ignition is on. This is the power to the radio. The other wire is for the clock/memory, and should be connected to a post which is always hot (energized) whether the ignition is on or not.

Hope this helps.

Mickey
 
The Ignition wire you will pro find is a green/brown (I think?) in the harness right behind the radio. The power line should be hooked up to one of the purple wires in the harness. The power circuit is for the built-in clock and the memory setting for the tuner, which need power to retain the presets. You should also have a black, which will be connected to any good ground point. The other wires should be to the speakers and the antenae.

I would also recommend that you hook up an line fuse onto the ignition wire. Further, if you tape the fuse holder to the rear of the radio, that will help to keep it up and out of the way when installing through the console and metal support peice.

Make sure the keep the wire out of the way of the transmission dip stip too.

Bruce
 
seems complicated but after messing with this stuff for a while you will get the sense of it. For something to work you generally need a hot wire and a ground wire...though some things work because the fixture (rear lights) are grounded and don't need a ground wire. There are several hot circuits....green -- hot, switched (on when ignition on) and fused at the fuse block, brown -- hot all the time, unfused, purple -- hot all the time and fused, red -- hot through switch from brown, etc. etc. As you read wiring diagrams (sick pastime done through necessity only) you start to see this.

These guys have it right. Only thing to add is it may depend on the year. Always post the year of your car. My 69 only uses the purple circuit through a fused wire to the radio and a ground wire because I don't have a new type radio. You can play the radio with the engine off that way but you can also leave it on and run the battery down if say you turn the volume down, forget to turn it back up and leave it on. There are some issues with the power circuit for the built in clock. If you disconnect the battery to work on the car or have a battery cutoff switch (very good idea) you have to reset the clock and memory each time. There is a way to route a second circuit around the battery to prevent this if you search this site and other sites archives. Guess that's how it's done in modern cars with a very low fuse on the bypass circuit. Guess that's getting complicated for now. There should be a purple wire that drops down off the main harness in the console extension group of wires that you can plug into as they say. Not sure about the green/brown location as I don't have it on mine. All my green stuff goes through the hazard switch but you might have one on yours. Get to know your wiring diagram...get a color one.

More than you wanted to know at this point, probably.
 
Even more... I have a switch to manually trigger the auxiliary/electric cooling fan in front of the radiator - mounted under the radio (where the seat-belt warning lamp was I think). To balance the look of the panel I had a spare, unused rocker switch in the other hole. I ended up using the 2nd rocker as a radio on/off switch that runs a relay, which in turn eventually turns the radio on/off. I designed the wiring harness so the relay can be plugged into a high amperage line direct to the battery in the event that I wired an amp into the system - either way, the switch is isolated (and fused) and the radio can be run without the ignition on.
 
Would that guide apply to a Midget 1500 as well?
 
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