Registry of Ex Military Land Rovers

Land Rovers => Australian "Perentie " 110 & 6x6 Vehicles => Topic started by: gooloo on June 12, 2016, 03:56:47 PM

Title: cigarette lighter voltage
Post by: gooloo on June 12, 2016, 03:56:47 PM
so I couldn't work out why the cigarette lighter works but nothing I plugged in to it would work.... (phone chargers, uhf chargers, etc)

Put a multi meter onto it and it's 11.5 volts. Put a multi meter onto the lucas plug and it's 12.5

before I start pulling stuff apart can someone else with a 6x6 do me a favour and check the voltage on their cig lighter?

if it's all too hard I'll just make an adaptor off the lucas plug..... but I'm curious to know if this is "normal"?
Title: Re: cigarette lighter voltage
Post by: dugite on June 12, 2016, 04:39:01 PM
It CAN occur if you have a dual battery system and the cig plug is wired from the 2nd battery AND if either that 2nd battery is stuffed OR the dual battery system management is not working correctly  :)
Title: Re: cigarette lighter voltage
Post by: gooloo on June 12, 2016, 04:41:14 PM
No dual battery.... (As far as I know) bog standard straight from the auctions
Title: Re: cigarette lighter voltage
Post by: dugite on June 12, 2016, 04:41:44 PM
I'm a little surprised that the accessories you list do not work off 11.5v - are you fitting the plugs fully?
Title: Re: cigarette lighter voltage
Post by: dugite on June 12, 2016, 04:51:19 PM
Ah well scratch that - I had a very similar thing as you have got with my RSFV - but in my case the 2nd (aux) battery was stuffed   :)
Title: Re: cigarette lighter voltage
Post by: gooloo on June 12, 2016, 04:57:12 PM
I'm a little surprised that the accessories you list do not work off 11.5v - are you fitting the plugs fully?

Yeah I was surprised as well... I tried 3 or 4 different plugs cos I thought maybe they weren't seating properly or something. I checked with a cig to double cig adaptor thing and I'm getting the 11.5 through to the adaptor so it's not a plug seating issue.... It seems iPhone chargers and usb chargers won't run without the 12+ volts

The weird thing is.... Why am I only getting 11.5 at the outlet????
Title: Re: cigarette lighter voltage
Post by: Dervish on June 12, 2016, 05:10:58 PM
You're measuring 11.5V with the multimeter as it is a high impedance load i.e. it draws almost no current. If you were to wire up a bulb to the socket, then measure the voltage across it you'd get much less. This is why most mechanics use test lights rather than multimeters. You've got resistance in the circuit somewhere and it must be fairly local to the lighter socket; a dodgy earth or loose connector - it should be an easy fix.
Title: Re: cigarette lighter voltage
Post by: gooloo on June 12, 2016, 05:36:30 PM
Yeah I started with the test light and it was fine.... But still nothing that I plugged in would work - that's when I went for the multimeter

Will pull the panel off and check the voltage coming in to the socket.... The actuator for 6wd is on that same panel so hopefully there's enough slack in that cable to get the panel out far enough
Title: Re: cigarette lighter voltage
Post by: 303Gunner on June 12, 2016, 09:52:56 PM
Will pull the panel off and check .... The actuator for 6wd is on that same panel so hopefully there's enough slack in that cable to get the panel out far enough
The centre diff lock/6wd "switch" is actually an air valve, and the "Cable" is a vacuum air line. The lines are secured with a re-usable compression fitting and it's a simple matter to undo them to get extra reach on the front panel.

Can't help with the voltage issue. Are your fuses the early glass tube type, or the later blade type? Glass tube fuses are notorious for corrosion between the holder and the fuse causing high resistance.
Title: Re: cigarette lighter voltage
Post by: gooloo on June 13, 2016, 09:17:54 AM
The centre diff lock/6wd "switch" is actually an air valve, and the "Cable" is a vacuum air line. The lines are secured with a re-usable compression fitting and it's a simple matter to undo them to get extra reach on the front panel.

Can't help with the voltage issue. Are your fuses the early glass tube type, or the later blade type? Glass tube fuses are notorious for corrosion between the holder and the fuse causing high resistance.

good to know - thanks for that....
i've only found the fuses in the centre panel so far and they're blades. It says on that panel that the fuse for the cig lighter and some other stuff are inline and under the ashtray. I pulled the ashtray and saw a bunch of wires but couldn't clearly see any inline fuses but I did only have a quick look.... will pull the panel out and have a better look.