Proper wiring for Radio..., Motorola model Options

[Baumgardner]

I posted earlier about this radio but have more information now...

It is a Motorola and was original to the car. It was not connected or wired when I got the car. I sent it out and it works fine and I'd like to reinstall it since it was original to the car (don't really care if it doesn't sound great because I don't listen to the radio much at all but would like it to work). I have done some research on Motorolas installed in 914s and VWs. Most bear the Sapphire label although mine doesn't. I've also researched these wires:

a. The brown is obviously the speaker wire which will need to be wired in parallel for mono.

b. The black wire is the main power.

c. The blue wire illuminates the radio and is meant to be tied into the dash lights.

d. The radio did not come with a ground - ground was meant to be suppled by the attachment to the wall in back.

Question 1: I planned to connect the black power to the red power in the cigarette lighter. Does it matter that I don't have a ground connected to the lighter from the radio or do I need to run a wire from the radio rear clip to the cigarette ground? (Obviously, I am no electrician).

Question 2: Where should I attach the blue wire that is meant to tie into the dash dimmer switch? The blue wire connects directly into a tiny light bulb inside the radio.

Question 3: Should I put an inline fuse for protection into the black and/or blue wires and if so how many amps?

Thanks so much for any help... I'd hate to blow the radio up reinstalling it.

- Michael

[Johny Blackstain]

Not sure, but think the blue wire is for a power antenna. It can't hurt to install an inline fuse & while it's out I'd try cleaning the pots with some CRC electrical contact cleaner. I believe I used the lighter as well for the power source of my "mono" Blaupunkt.

[Baumgardner]

Not sure, but think the blue wire is for a power antenna. It can't hurt to install an inline fuse & while it's out I'd try cleaning the pots with some CRC electrical contact cleaner. I believe I used the lighter as well for the power source of my "mono" Blaupunkt.

Johny, thanks... the only reason I know for sure the blue is for illumination is that if I open the radio the blue wire is only attached directly to a small bulb in the front of the radio... and I think this was common with the Motorola Sapphires....

[Johny Blackstain]

Not sure, but think the blue wire is for a power antenna. It can't hurt to install an inline fuse & while it's out I'd try cleaning the pots with some CRC electrical contact cleaner. I believe I used the lighter as well for the power source of my "mono" Blaupunkt.

Johny, thanks... the only reason I know for sure the blue is for illumination is that if I open the radio the blue wire is only attached directly to a small bulb in the front of the radio... and I think this was common with the Motorola Sapphires....

Well there's no arguing that. Many old radios had an extra wire for a power antenna option, but I never saw one for a dimmer control until now. No need for an extra wire to the lighter ground if you use the back chassis mount.

[michael7810]

If you take power from the cig lighter you don’t need an in-line fuse. There is a instrument light wire going to the gauges under the dash. The one to the CHT will be easy to locate as it goes to a lightbulb. Just ground the radio thru the rear mounting bracket. No need to ground thru the cig lighter.