[TR] Not good with electrical

[Jim Muller]

On 25 Aug 2009 at 17:49, thenicholls at verizon.net wrote:

> If I select volts and attach the two leads to where the bulb plugs
> in, it should show something if it is getting power, and nothing
> if it is not getting power, correct?  I don't want to fry anything.

If the meter isn't broken it won't blow anything, so don't worry 
about that.  If you have the wires attached backwards, the meter may 
try to jump backwards if it is a needle and meter display, or the 
digital display may show a negative voltage, but that's okay too.

If you just have a burned out bulb, you should see voltage between 
those terminal.  But maybe you won't see any voltage at all.  It is 
possible the wiring isn't right and the bulb is fine, or both could 
be a problem.  For example, the ground side (i.e. the "negative" 
side) may simply have a poor connection to ground.  I don't know what 
the TR6 trunk switch is like, but the one on my Spitfire sometimes 
just doesn't make good contact to ground unless it it is jiggled a 
bit.  A problem like that would make the reading be zero.  Maybe you 
don't even know which terminal is positive and which is ground.  So 
another test is to attach the meter's negative wire to a good chassis 
ground, not paint, then touch the other wire to each of the terminals 
in the light socket.  When you touch the positive side the meter will 
show it.  If neither side shows a positive voltage and you are 
absolutely sure your ground connection is good, then the problem is 
in the wiring that feeds power to the socket.

-- 
Jim Muller
jimmuller at rcn.com
'80 Spitfire, '70 GT6+