Author Topic: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL  (Read 1261 times)

PeterW113

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I am installing a new radio which requires as Switched Live feed.

Reading through various posts the nearest Switched Live is the cigarette lighter, however access is very tight preventing me from cutting into the CL switched live and "piggy backing" off of it.

I have unplugged the cigarette lighter plug, and wondering what is there some other two pin pug/adapter that could be inserted in between  the original two pin plug and the CL that would allow me to take off a live feed.

If anyone has a suggestion or better solution I would be grateful to hear?

Thanks in advance - Peter
Peter
1968 MB 280SL, RHD Auto
1968 Lotus Elan +2
1962 Ford Thunderbird
2007 BMW 1200 GS

Peter h

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08.68 280sl automatic white 717 G  blue MB Tex
09.68 280sl  4-speed, now 5-speed Getrag 180 G dark green MB Tex

PeterW113

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #2 on: December 30, 2024, 08:35:40 »
Excellent thank you,

I will get that ordered.

All the best,

Peter
Peter
1968 MB 280SL, RHD Auto
1968 Lotus Elan +2
1962 Ford Thunderbird
2007 BMW 1200 GS

BobH

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #3 on: December 30, 2024, 16:42:53 »
Hello, don't forget the cigarette lighter only gets power when the ignition is on, or the engine is running.  if you want to listen to the radio without the ignition on, there is a terminal on the ignition switch on 280's, "R", which is powered when the key is turned, but without the ignition on, so you won't risk leaving the radio on when you leave the car

Have a look on here, i understand this terminal is prewired to the ancillary fuses in the engine bay, i'm not sure if there is then an output wired from the fuse to the radio position, of if you need to wire from there yourself.  Alternatively you could just wire directly from the R terminal on the ignition switch, with an inline fuse

https://www.sl113.org/wiki/Electrical/Radio#RadioInstall
February 1965 230SL Automatic
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Peter h

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #4 on: December 30, 2024, 17:09:31 »
Of course you should operate the radio using the extra fuse on the right in the engine compartment.
I used the adapter to power a USB port in the footwell.
Peter
08.68 280sl automatic white 717 G  blue MB Tex
09.68 280sl  4-speed, now 5-speed Getrag 180 G dark green MB Tex

PeterW113

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #5 on: December 31, 2024, 17:52:06 »
Many thanks Bob & Peter for your comments.

My car originally had a aftermarket radio fitted so I am using its permanent live feed with an in line fuse. I have not yet been able to identify the source of the live feed but it works for now, although I will look to see if using the "additional fuse" approach as is being suggested is a better way go.

I accept that using the cigarette lighter as a switched live feed is not ideal, so I will look at removing the ignition switch to see if I can access the terminal marked R as this would be the ideal choice.

Thanks again and all comments are well received.

Cheers Peter
Peter
1968 MB 280SL, RHD Auto
1968 Lotus Elan +2
1962 Ford Thunderbird
2007 BMW 1200 GS

Pawel66

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #6 on: December 31, 2024, 20:01:49 »
Take a look here for radio wiring: https://www.sl113.org/forums/index.php?topic=27466.msg197177#msg197177

You have all the wires in the harness, you may just need an auxiliary fuse box as indicated earlier. You may also need to run a wire through the grommet in the firewall, next to wiper motor, from fusebox to radio.
Pawel

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PeterW113

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Re: Connecting to Cigarette Lighter Switched Live - Radio - 280 SL
« Reply #7 on: January 02, 2025, 17:54:12 »
Many thanks Pawel,

Despite first reading as many posts as I could find, I still managed to miss your post!  Now having read it,  I have now ordered the auxiliary fuse box and will explore the harness for the said wires at the weekend.


Cheers Peter

Peter
1968 MB 280SL, RHD Auto
1968 Lotus Elan +2
1962 Ford Thunderbird
2007 BMW 1200 GS

PeterW113

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Whilst I wait for my auxiliary fuse box to arrive, I made this adapter as a temporary solution. It fits in between the harness and cigarette lighter providing a power take off for the Radio, albeit the ignition key has to be in position 2.

Overall I am quite pleased with the Retrosound Europa radio.
Peter
1968 MB 280SL, RHD Auto
1968 Lotus Elan +2
1962 Ford Thunderbird
2007 BMW 1200 GS