Western Patrol Club Inc.
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Just had a young fella from the national forum drop around who was having issues wiring up spotties on his MQ.

The vehicle is set up from factory to switch earth not 12 Volts for the Headlights... wouldna believed it if I didn't see it...

Do you mean earth was to + ?

Yep...

The 'common' terminal (the one that is earth on GQ/GU) has 12 Volts on it all the time.

With headlight switch selected 'Off" both the hi and lo terminals have 12 volts on them as well so no workee.

Select Lo beam and the Lo beam terminal drops to earth and Hi beam stays at 12 V so Lo beam comes on.

Select Hi beam and the Hi beam terminal now goes to Earth and Lo beam goes to 12 volts so Hi beam comes on.

Some of the early jap cars did it that way but I swear my old MQ was "normal" 

Yeah mate, my MQ was normal as well.
I have a Nissan workshop manual for the MQ here somewhere  I will dig it out and see what it says.

Thanks Bluey,

Sure is a handy one to keep in mind. I was going to show the fella how smart I was by picking out the "after market wiring" some "prev owner" had "balls'd up"... but... there wasn't any 

It was all kosher 

When it stops raining for half a minute I'll dash down to the shed and dig out  the manual.
I do know that there were some earlie pommy vehicles (1940's and earlier) that had positive earth but this one is out of left field

ET is it a 24 volt system with 2 12 volt batteries in series? If so then the centre point which would be +ve on one battery & -ve on the other would be earthed to pick off 12 vots.


I was told once that Rolls Royce always do +ve earth because it apparently prevents corrosion in the radiator. My first mini was +ve earth.

Cheers

Bri

I was told once that Rolls Royce always do +ve earth because it apparently prevents corrosion in the radiator. My first mini was +ve earth.

Cheers

Bri
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Is that what you called your first Jeep? (they are small)

Nope...

Its a standard 12 Volts, negative earth vehicle with +12 WRT earth (and the batt -ve) on the "common" terminal and the Lo or Hi terminals go from +12 V WRT earth down to Earth when that Headlight filament is selected.

Yeah, A lot of early pommy vehicles were positive earth. Being apprentices in the late 60's early 70's meant that the cars we drove were all even older than that and probably about a 1/3rd at the time were positive earth pommy or euro things, Simca's, Vauxies, lotsa Morries, couple of Gogomobiles... made for some interesting rewiring when peole put -ve earth 'Australian' radios etc in them. Indeed I recall that many accessories made at the time were available as positive or negative earth.

I can remember some fun and games as well mate  Sorry ET, nothing in my manual 

After I turn my 'guvvie limo' on, the headlights magically come on after about 10 seconds and after I turn it off, they magically turn off after about 10 seconds - just enough time to get the key in the door.  LOL

Yes, Big Brother is watching and knows you have paid up