Car lighter socket

[andygill]

Is a mains tester the same thing as a continuity tester ?

No, mains testers test for the presence of mains voltage. I recommend getting a proper digital multimeter, ideally one with a buzzer on the continuity setting. I was amazed recently to find very basic digital multimeters for sale in a local pound shop (I bought one and it seems to work OK).

Is this any good ?

http://www.screwfix.com/search.do?_dync ... 12&x=8&y=7

or should I stick with

http://www.maplin.co.uk/Module.aspx?ModuleNo=7030

Thanks

[alex_holden]

http://www.screwfix.com/search.do?_dync ... 12&x=8&y=7

I can't tell from the listing whether it has a continuity buzzer. Oh, one of the user reviews says that it does.

This one looks OK too, and it's a bit cheaper:
http://www.screwfix.com/prods/34028/Ele ... Multimeter

[mixtboy]

if you cut off the end (the plug part) of the multi socket unit in the image above, doesn't that mean you've also cut out the fuse in the plug section? doesn't it need a fuse in it for safety? and which point is the best part of the wiring loom to connect it to the positive live source?

[bmcecosse]

Connect to fuse box - either constant ON -or the IGN switched fuse.

[Nuffles]

I bought one very similar to the second one you originally posted. I cut out a square of 3mm alu about 4x4cm and cut a hole big enough to mount the lighter in, then drilled two small holes under the dash just above the passenger's right knee. Bolted it on and it now hangs in a very accessible place for sat nav/phone charger/inverter. I hooked it up to the dash lights the other day too so it lights up at night as well I took a live from the ignition side of the fuse box and earthed it to the bolts I used to bolt it to the bottom of the dash and it works a charm.

I bought a multimeter from a small electronics shop for about a tenner and although it doesn't have a continuity tester (that I know of? may have to look for that) I just use the resistance tester. It says one with 100% resistance (ie, the prongs touching nothing) down to 0 for no resistance at all (if you make a continuous circuit). Having something with a buzzer would be useful though... I wonder.

[MarkyB]

I don't like the sound of "hangs in a very accessible place".
Equates to the wire is free to move across the edge of the under dash panel until it wears through the insulation and shorts out, at best blowing a fuse, at worst getting very hot and catching the tinder dry sound proofing alight

Please tell me this isn't the case.

[andygill]

Hi Nuffles

Any chance you could post some pictures.

Cheers
Andy

[Nuffles]

By 'hangs in an accessible place' I meant the metal plate I made hangs below the dash - but is securely bolted to it. I have an oil pressure gauge bolted to the bottom of the dash in the same way by a previous owner but my right knee manages to block it almost entirely from view I'll get pictures today, but they won't be up until this evening as I'm at work until 4:30ish

[nigelr2000]

Just had a look at the specs for the 4 way adapter and it only supplies 500 mA (1/2 an amp) per socket so would be no good to run higher power applications like a power inverter, halogen worklight or even a cigarette lighter !!

If you want to run higher power (I think a standard fag lighter is rated up to 8 amps) use a standard metal socket.

[rayofleamington]

just a word of warning to those who are still learning their way around vehicle electrics:
A digital multimeter can confuse the heck out of a simple or clever person, if they are not careful!

Reading 12V (e.g. 12.6v) when a wire is 'live' does not mean that the circuit is any good!!
One great example is the horn circuit - I could read 12v at the column switch (where it is grounded when pressed) but the horn didn't work - when I used a bulb test circuit it was immediately obvious as the bulb wouldn't light up. The answer was that the column slip ring and brush were making a very high resistance contact (only needed some brasso) - however the high resistance did not stop the meter from reading live.
The bulb will only light up if the circuit can transmit a decent current (i.e it works) and a meter will read 12v even with a very bad connection as long as it is not completely disconnected (i.e. no guarantee that it works)

I've got a 20w bulb in a socket with 4 foot of wire and crocodile clips on the end - you can use it for checking the points / ignition timing , checking circuits and also as a lamp for working on the car away from home, as it is easy to store in the glovebox.

[MarkyB]

"securely bolted " is fine, I had visions of a socket dangling by the wire when you said it hangs.

[Nuffles]

This is how I have mine set up -
As seen from the driver's viewpoint:


And seen from underneath showing how it's attached:

[MarkyB]

I hate to be critical, but I'd take a file to those sharp looking corners.
Not health and safety gone mad, honest.

[Nuffles]

Not sharp - honest!

I went around the edges with a file to take off the jigsaw edges and did the corners at the same time. I may take it out at some point and do 45* angles on the corners but it wasn't a fun job getting the bolts in and done up so not really looking forward to taking it out :/ It's quite out of the way under there and as much as they are square corners they're not 'sharp'.

[d_harris]

Just as an aside, what rating of fuse do people use in the fag lighters?

[Nuffles]

I have a 10 amp in the wiring for mine I think - possibly a 15.