A simple test for a bad ground:

Get a DVM (digital vote meter) which can be had at most aftermarket parts
stores from $10 to $25 bucks.

Run a ground lead to the negative post on the vehicle battery.

Turn on the lights and check the voltage to the GROUND side of the bulb.
(also a good idea to check the positive side of the lamp as well to
eliminate bad connections on the hot side).

Note these test should be run with the lamp in the circuit.

Second test is with between the negative side of the battery and the chassis
ground then between the negative side of the battery and the engine block
(most have different ground systems)

Anything more than a few mille-volts is suspect.

Last and a bit off topic: check the voltage between the metal frame of the
radiator and the negative side of the battery. Older vehicles have a
tendency to produce electrolysis that will eat away at the aluminum in the
radiator with the result that the radiator fails usually at the most in
opportune time)


----- Original Message -----
From: "Annette and Charlie Barker" <k5pgs@...>
To: <rv_communications@yahoogroups.com>
Sent: Sunday, July 05, 2009 8:50 PM
Subject: Re: [RV_COM...] tail light booster question


:I ditto the comment Dave made about the dirty lens, although you
: probably have a bad ground somewhere. We were pulled over by a couple
: of officers in the Orlando area a while back and the commented that
: the illumination for the license plate was supposed to be such that
: it could be read from a certain number of feet away. I don't remember
: the number, something like 45 feet or so... I wanted to smart off and
: ask them if they had calibrated eyeballs to tell how far away they
: were when they read our plate, but I didn't think they would think it
: was funny. Anyway, the next day I pulled it apart and found that
: there was an accumulation of dirt inside the lens! Seeing Dave's
: reply below brought a chuckle to me when I remembered that occasion.
:
: Hope its something simple.
:
: Hugs from Houston,
:
: Charlie B.
:
: At 01:34 PM 7/5/2009, you wrote:
: >Over the years,I have owned three vehicles and a utility trailer
: >in which the tail lights went dim. In every case, I found that
: >dust or dirt has gradually accumulated on the inside of the tail
: >light lens.
: ><SNIP>
:
: Please take a moment to help advance research seeking a solution to
: the sneaky silent killer, Pancreatic Cancer!
: Go to: http://www.pancan.org/Public/take.html and quickly contact
: your Senators and Representative to request funding increase.
: A sincere thanks from Annette and Charlie Barker
:
:
:
: ------------------------------------
:
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