Jump to content


Photo
- - - - -

Multimeter


  • Please log in to reply
2 replies to this topic

#1 Dangleeballs9568

Dangleeballs9568

    On The Road

  • Noobies
  • PipPip
  • 37 posts
  • Location: Swansea

Posted 01 September 2014 - 07:57 AM

I have been having issues with my headlights and have tried everything to get them working again. Have just purchased a multimeter and was wondering what is the best way to check the power through the wires from the switch to the bullet connectors and from them to the lights. I have a 1980 Austin Mini

#2 KernowCooper

KernowCooper

    Sparkie

  • Mini Docs
  • PipPipPipPipPipPipPipPipPipPip
  • 7,847 posts
  • Name: Dave
  • Location: The South West
  • Local Club: Kernow Mini Club

Posted 01 September 2014 - 01:16 PM

Here is the full circuit with the wiring colours in the picture for you.

Attached Files



#3 nz_seamless

nz_seamless

    Stage One Kit Fitted

  • Noobies
  • PipPipPip
  • 68 posts
  • Location: Wellington

Posted 02 September 2014 - 01:29 AM

If you haven't used a multimeter then what you want to do is use the voltage function, and remember that what a voltmeter is measuring is a difference between two points. Since it's measuring differences, if you put a volt meter on something at 6v and something else at 12v, the meter will show 6v - the difference. That's what they do.

So if you put the positive (red) probe on the live wire (according to the colours on your diagram) leading into the headlamp, and the negative (black) probe on any sort of earth connection, you expect to see battery voltage ~12v.

 

If you get zero, then that means you have no voltage arriving there, so go back to the switch and do the same thing, probing the wire you expect to be live, and referencing against any convenient earth point. I use exposed screw and bolt heads a lot when I need an earth. Anything that will form an electrical pathway to the car body, which is grounded.

If you get voltage at the switch but not the lamp, the issue is between those two points, though to be far if that was happening you have a short, and it likely would have blown a fuse anyway.

If you have nothing at the switch, go back to the fuse block, working your way back till you find voltage. Then look at what might be stopping it getting further.

 

Have fun, be patient. 






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users