Replaced Cigarette Lighter Socket with Dual USB Power Outlet Socket

[Gordo2]

My 1983 SC had a Euro / size B cigarette lighter socket - which is slightly larger than the US size A standard. As such, when I tried use it to power accessories - the cigarette power adapter plugs would wobble loose and the power would toggle on and off.

I tried using various USB / cigarette lighter adapters - but they were just too loose in the socket. The only way I could get a consistent power connection was by wedging something between the plug and the socket.

I found some older Pelican threads that suggested buying or making an adapter / sleeve that inserted into the cigarette lighter socket - but I was unable to find any adapters online.

My winter 911 projects theme has been "fix stuff that annoys me" - and this was on my list...

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Replacing the Cigarette Socket with a USB Power Outlet Socket

I picked a USB socket on Amazon (Cllena Dual USB Charger Socket). I chose this one because I liked that the outlets were lit / easy to find at night. I didn't really consider the size - but we'll get to that:



Working in the trunk - I removed interior blower assembly cover in order to access the backside of the lighter. The backside of the lighter is difficult to access, but I was able to reach the wires and remove the ground spade connector and male power pin connector from the lighter socket using a long needle nose pliers (and a bit of contortionist maneuvering).

Once the wires were removed, I was able to place my finger inside of the lighter socket and spin it (lefty loosey...) out of the retainer body.


Once the lighter socket was removed, I was able to pull / remove the retainer body from the trunk.

Upon removal - I suddenly realized that size matters... The stock / original cigarette socket is ~ 28mm in diameter, while the USB socket that I purchased was 29mm. I debated ordering a different USB socket, but decided I would enlarge the firewall hole by 1mm with a circular file.

I broke out my chainsaw blade sharpening file and enlarged the metal cigarette lighter hole (firewall) just enough to allow the USB socket to fit through it:



After I had filed & enlarged the hole, I made a J-hook out of a piece of wire and fished the lighter power and ground wires through the hole.

The spade connector on the ground wire fit onto the USB socket without modification. I cut off the male power pin connector, stripped the wire, soldered the end and crimped on a spade connector.

Threading the large plastic retainer nut onto the USB socket was somewhat of a challenge. The job would be much easier if the stereo head unit were removed - but I wasn't up for all that.

Working below the dash, from the passenger floor - I managed to get the nut in position and held it there by inserting a screwdriver through the lighter hole and nut. Once the nut was in position, I then fished the power and ground wire through it, and attached them to the USB socket.

Again from below the dash, I used a long screwdriver to position and spin the nut onto the USB socket body. Getting the threads started was a little difficult, but once started the nut tightened nicely (the outer edge of the nut has nubs that can be pushed with the screwdriver to spin / tighten the nut).

And finally - the done deal:


The USB socket that I purchased has an attached rubber, flip-up cover:


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No more loose USB power connections - one less thing to annoy me...

Gordo

[DaveMcKenz]

Nice job. Looks very discrete and classy.
Thanks for sharing,
Dave

[blucille]

Was considering this too, but decided I wanted the luxury to plug in a tire inflator or other standard automotive accessory.

Replaced the seat belt and brake warning light with a dual usb charger instead.

[AHudson]

Really nice job and write up. This too bugs me, but I've not taken the time to address it. Now I know where to look if I do!

I also appreciate the special quality of personal modification that seems simple on the outside, but takes time, thought, and contorting to get just right. Well done!

[old man neri]

I think I am going to try this but with this USB charger. It has a volt meter built into it.

[BlueJaybird]

Excellent job Gordo!
This is going to be valuable info to many of us.
Thanks for taking the time to post it here.

[Jack Stands]

Back in the day, Passport radar detectors came with this nice adapter.

[HorstP]

there is a certain risk that the 12V to 5V step down converter in these USB sockets generate significant radio interference. Specifically with the radio antenna being part of the windshield this can degrade radio performance quite significantly. Something one might check before committing to install it.

[Canada Kev]

Originally Posted by Jack Stands

Back in the day, Passport radar detectors came with this nice adapter.

I bought an Escort detector years back but it didn't come with the adapter. They did offer them as an accessory, but no longer. Thankfully, I bought one, but wish I had picked up a couple more especially as they were so damn inexpensive.

[Norm01]

Originally Posted by old man neri

I think I am going to try this but with this USB charger. It has a volt meter built into it.

Could you post a link to that. Looks great.

[old man neri]

Originally Posted by Norm01

Could you post a link to that. Looks great.

https://www.amazon.ca/MICTUNING-Digital-Display-Voltmeter-Charger/dp/B01M4OKBSB/ref=sr_1_7?ie=UTF8&qid=1520190444&sr=8-7&keywords=usb+charger+voltmeter

[porche]

.
FWIW, I’ve used this plug-in Voltage and USB port unit for many years in my ‘79 without any problems. It plugs securely right into the original cigar lighter unit in the car without issues. I like the ability to have a Volt Meter, that Porsche failed to include on our early cars, to monitor for the always dreaded overcharge issue and still be able to keep my iPhone charged
Bought mine on Amazon, but there's plenty currently on eBay. Attached a link, no affiliation, as example only - https://www.ebay.com/itm/Stinger-Car-12V-Digital-LED-Voltage-Meter-Plug-with-USB-Charger-SGP12/112818038351?epid=2255928415&hash=item1a447aa64f:gkgAAOSwqi1al1GP#rwid
..

[OldSpool87]

Great installation. General question on this type of voltage meter installation: does the lighter location give an accurate a reading of system voltage?

Thanks

[RSBob]

Originally Posted by porche

.
FWIW, I’ve used this plug-in Voltage and USB port unit for many years in my ‘79 without any problems. It plugs securely right into the original cigar lighter unit in the car without issues. I like the ability to have a Volt Meter, that Porsche failed to include on our early cars, to monitor for the always dreaded overcharge issue and still be able to keep my iPhone charged
Bought mine on Amazon, but there's plenty currently on eBay. Attached a link, no affiliation, as example only - https://www.ebay.com/itm/Stinger-Car-12V-Digital-LED-Voltage-Meter-Plug-with-USB-Charger-SGP12/112818038351?epid=2255928415&hash=item1a447aa64f:gkgAAOSwqi1al1GP#rwid
..

Use the same and it works great with continuous easy to see readouts. I prefer this in case of a flat, since I still have the original port for the tire inflator.

[Gordo2]

The version with the voltmeter is pretty cool - probably would have bought it had I seen it first.

Also - although I didn't mention it, I have a cigarette lighter socket installed / mounted under the passenger seat. I installed it quite a while back as a power source for my Innovate LM2 wideband (I normally keep it plugged in). Not really a convenient location to access to charge a phone or power a GPS - but it's available if I ever need access to a lighter socket (i.e. mini-compressor).

Thanks for the comments & feedback folks,

Gordo

[Flojo]

nice... but why so complicated?
just pull the lighter and insert a micro USB dual charger. done




as you can see, you se nothing...

[Gordo2]

Originally Posted by Flojo

nice... but why so complicated?
just pull the lighter and insert a micro USB dual charger. done

I tried a variety of micro usb plugs like the one you posted, but each would wobble in the socket and lose power.

If yours works - more power to ya

Gordo

[dad911]

Originally Posted by Canada Kev

I bought an Escort detector years back but it didn't come with the adapter. They did offer them as an accessory, but no longer. Thankfully, I bought one, but wish I had picked up a couple more especially as they were so damn inexpensive.

That begs to be plastic printed.

If you have a set of calipers, I'll give it a try.

[Jonny H]

Originally Posted by OldSpool87

Great installation. General question on this type of voltage meter installation: does the lighter location give an accurate a reading of system voltage?

Thanks

Typically, the lighter location reads about 0.2V lower than the battery voltage.

[Chuck.H]

These are all great solutions, but I'll share my simple one - I just jam a small piece of rubber under one of the side ground contacts, so that it's enlarged the diameter enough to fit tightly.

HTH!
Chuck.H
'89 TurboLookTarga, 439k miles