Welcome to our resource for MG Car Information.



MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - 'New' radio installation?!!

I am planning to install a brand new radio in my '58 Coupe. What is the best way to wire it?
gerard hutchinson

Read the instructions that come with the new radio. If the manufacturer can't tell you how to install it successfully, send it back. Be aware that you will likely have to convert your electrical system to negative earth, if it has not been done already.

Out of curiosity, I would like to see a copy of the manufacturer's installation instructions.
Barney Gaylord

Modern radios generally need 2 power supplies. One is for the "memory and retains preset stations and set up values whilst the second one switches the radio on and off.

I put both these 2 supplies to the same point and these are "hot" when my isolator is on. Because I wired mine in this configuation when I switch my isolator off my radio loses its memory. However if I were to fit the memory supply to a hot point before the isolator switch then the memory would be retained.

I did not do this as when my car is parked in the garage it may reside there for perhaps a month or so in which time I feel the memory supply would flatten my battery so on powering up I reprogram my player.
Robert (Bob) Midget Turbo

Bob, you are correct!

My radio needs a continuous power supply. Besides a direct connection to the positive terminal on the battery where can I find a power source?
gerard hutchinson

There is conitinuos supply at the horn fuse, assuming of course you have checked that the polarity is ok
Graham M V

If you want to wire it as intended then you should wire the continuous supply to the always on fuse (as described by Graham). Then conect the player on supply to the other fuse, in this manner the radio/cd will retain its memory when switched off. However it will lose its memory if you remove or isolate the battery, you would then have to reprogram it when the battery is reconnected
Robert (Bob) Midget Turbo

Modern radios also usually have a third supply for the illumination, usually off the parking or dash lamp circuit. R or RW
Always ON = browN or browN/Green
Key ON = White or Green

All of these should have dedicated radio rated fuses.

FR Millmore

I have only ever seen one aftermarket radio/cd with a connection for illumination. It did not illuminate the face but actually it was the sensor and dimmed the face plate when the lights were on. I thought this feature was only on factory fitted radios?
Robert (Bob) Midget Turbo

Well, Gerard? Is this a teaser test? Do we get to see the installation instructions, or are you kidding us about this being a "brand new" radio?
Barney Gaylord

I could not get a picture to upload but the link below includes the wiring schematic.
gerard hutchinson

So you have now easily doubled the number of wires in an MGA, or maybe quadrasexrupled if you install all the other crap.
Similar to every one I've touched in the last ten years - about 8.
For Bob, that includes the "illumination" lead.

Worst part is, I can never remember how to operate the damn things, and they are all "just enough" different that even changing cars means I can't find a radio station or in some cases, even turn the thing
OFF. I bought a car, and while driving it home in the dark could do some radio functions by pushing buttons on the radio, but others only with the remote - remote - WTF? Reset the clock & station presets because you had the battery disconnected? Ha!
I've taken to seeing what time it resets to (not all the same), and then disconnecting the battery at that time to set the clock. Of course, on a lot of modern cars that screws the ECU up!

Don't even get me started on the moving light show that keeps telling me what the name of the manufacturer is, but obscures the time or station it is on.

I thought it were because I'se a grumpy old fart, but even my daughter, who is of the "Button People" generation, can't operate most of what is on her car radio/CD/USB/IPOD, never mind the car she gave back to me last year.
Radios were good at two wires, two knobs, six push-pull buttons for station set (but you could ignore those)
I could operate a cassette player, and the first CD players were possible; no more.

FR Millmore

Well I must start using diagrams cos I have not noticed the description of the orange wire before because I don't use it.

When I install an after market radio I ignore the blue and the orange knowing that I don't want to operate an electric ariel etc. So I simply concentrate on the speaker connections and the 2 hot wires (red and yellow) plus nuetral.

This diagram tells me that the after market radios in the USA are exactly the same colours and connections as those we use in Europe. All of them use the same colours and the same connections

As stated I don't use the orange and blue leads but I suppose if you want the radio to operate an electric ariel or you want the display to dim then by all means connect them as per diagram.

Whilst all these after market radios are the same wiring not all modern cars are wired exactly the same and simply using the on board sockets and connecting to the modern vehicles electrical system may cause the radio to explode. :) In the UK this would be the case with some GM vehicles.
Bob Turbo Midget England


It's exactly the same with almost all modern consumer electronics. That's why my stereo at home is 25 years old and still has a proper remote control! with buttons for sausage fingers, writing that you can read wthout a microscope and a volume knob that you can TURN! (It's also 10 inches long and strong enough to do someone an injury and it has NEVER been lost down the back of the sofa!) Plus most of the new stuff sounds cr@p

And I'm not an old f@*t as I'm not yet 50!

dominic clancy

Last night I was able to wire the radio but still can not figure out how to wire it so that it DOES NOT turn on when the ignition switch is on! I thought I had it figured but failed. Secondly, the damn thing was not nearly loud enough!! It's supposed to have plenty of power and the speakers are right behind my head!! Do I have a gounding problem? Could the speaker terminals be wired backward? Help!!!
gerard hutchinson

Wiring the speakers backwards will not affect the volume.

Are you saying that when you switch the igniion on the radio switches on?

Which wire have you connected to the always live fuse and which has gone to the switched power fuse?

To hear a player in an MGA is very difficult. It depends on the quality of the speakers (should be more than 50w RMS and power output of the unit

What have you set the amp gain to?

Robert (Bob) Midget Turbo

Gerard, -- Thank you for copy of the instructions. As complex as it is, it seems to be well written and easy enough to understand. I have a few comments.
1.) What is purpose of a remote control for a car radio? A CD changer installed in the boot, maybe? If it cannot be operated without the remote control, I'd send it back.
2.) It requires a large watch battery. I don't care what it's for, but I would need to know where it goes, how to change it when it goes bad, and how often it may need to be changed? None of this is explained (deficiency of the instructions).
3.) No reason given for why it must be kept level within 30 degrees of horizontal. I would expect it work standing on end or upside down.
4.) Must ground it to the car chassis. Wouldn't this negate use of the (recommended) voltage inverter for positive ground cars? I cannot imagine anyone trying to instal this sort of electronic equipment in a positive earth vehicle (even though it implies that you can).
5.) One of the troubleshooting notes mentions "reset the receiver", but there is no explanation how to do that (deficiency of the instructions).
6.) Multiple notes saying "See page 22 of the instructions", but there is no page 22 here. This implies that you need some additional booklet which is not included with this device. Either a deficiency of the instructions, or that booklet would be provided with some other device when needed. If I ever saw a 22+ page instruction book with an electronic device, I'd send it back. Consumer product is not supposed to be that difficult.
7.) Near top of first page it clearly states, "If you have any questions or require information regarding installation kits, consult your JVC car audio dealer or a company supplying kits". Also, "If you are not sure how to install this receiver correctly, have it installed by a qualified technician".

Bottom line is, you're asking the wrong people. We don't necessarily know how to interpret this stuff any better than you do. You should be asking some JVC audio dealer for clarification of the instructions. All of this gets back to my first response, "If the manufacturer can't tell you how to install it successfully, send it back" (and maybe refrain from asking the blind to lead the blind).

Barney Gaylord

Well, I will finally use this:
Yes Dominic, you is a old fart. The blessed have such honour conferred early, possibly as has been said of me, before age 12 or 15.

Bob, never occurred to me that the "illumination" lead was a dimmer, I thought it was the actual light. I just hooked them up per instructions.
And No, they don't all use the same coloured wires. I have several different, probably spread over a ten year period, which may or may not matter. Might be manufacturers choice. When I put a new one in my daughter's car because she's a kid and MUST HAVE all that modern stuff, the wires were different to the old one. I put her old one in my car which didn't have CD, and the wires were again different. Both cars are Mazda 90-94 and the car wires were the same, but not matching any of the radios.
And, why they cannot come up with a standard so it (plugs) works on all cars is beyond me.

Gerard- To quote me "...or...even turn the thing
OFF." Look for a tiny unlabeled (or invisibly labeled!) button someplace; I have one with a tiny button in the top left corner - looks very similar to the button that sometimes on some units causes the face to jump off and fall in your coffee. Worse yet, it might take some arcane combination of buttons. What wire is connected where should not affect "Power On". Of course, now you have to try to find the instructions in English, and correct the translation from Yapanese.
Volume I can't help with, but it probably means you need to figure out how to set all that amp/equalizer/etc nonsense. And some of them have a "Mute" function, which certainly does kill the volume, but still leaves it playing.

FR Millmore

It's a simple Radio CD Barney not a saturn 5 rocket what is hard about it? all after market radio CDs are almost identical as they say it is not rocket science.

I suspect Gerard has not copied all the instructions the reset button is normally under the front face plate.

Most radios come with a remote control that is never used if you dont like it you throw it in the rubbish LOL.
Robert (Bob) Midget Turbo

Old Fart for you too!
1)Remote has much fewer buttons, and you can feel them in the dark at 80 mph on a rough road, and maybe do summat useful to your radio in flight. (If you can find it. The glue on the velcro melts and it falls off the dash in the summer, and now you know what the crunch was last week when you got in the car.) Can't do that with the 400 micro buttons, which are invariably just out of reach and inscrutable. Of course, you soon exhaust the capabilities of the remote, so you have to stop and get out your surgical lamp, magnifying glass, and the damned book, and figure out what to do so you can tune to whatever the signs say for the emergency road info just ahead.
2)for remote
3)The mice that turn the CD fall down into a pile at the bottom, and get pissed, and the resulting liquid shorts everything out.
For the rest, these are "installation instructions" NOT "operating instructions", that's a few dozen more paginas.

In counting pages, do you only count the bits in English, or do all the other languages count? I've seen as many as 10 maybe. I think the last (car radio) one I downloaded was near 100 pages.

"qualified technician" - Seen many of these lately?

FR Millmore

This thread was discussed between 27/10/2011 and 02/11/2011

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.