[DeTomaso] Bad Ground Symptoms....Maybe

[Doug Braun]

Michael,

	If your battery is dying over 7 to 10 days, and you're re-charging it with
a charger instead of by driving the car, it could be that your problem is
just a bad alternator or regulator.  Before you go looking for shorts that
may not be there, use a voltmeter to check your charging voltage with the
engine running at about 2500 RPM with the headlights on.  The voltage at the
battery should be between 13.7 and 14.3 VDC.  If not, you may have a bad
alternator and/or regulator.  Your local auto parts store can test your
alternator.

	If the car passes the charging test, check the water level in the battery
then fully charge it with a battery charger.  Then take it to your local
auto parts store and have them load test it.  It may be that you have a
dying battery.  Replace it if it measures bad on the load test.

	After you've passed the tests above, then start looking for shorts via
Larry's method below but since it takes 7 days to die the short may be minor
enough to not light the lamp that Larry suggests.  For a more sensitive
test, turn everything off in the car with the ignition key out and the doors
closed.  Disconnect the battery ground cable, set your multimeter to measure
current (10 to 20 Amp scale first) and use the meter to make the connection
between the battery's negative post and the ground cable's clamp.  If you
get a reading, you have a short.  If you get no reading, switch to the
mill-Amp scale on your meter.  If you see more than 20 milliamps or so of
current, you have a short somewhere.  You can then use Larry's method of
pulling one fuse at a time to locate the problem.

Doug Braun
blue 73L #550

-----Original Message-----
From: detomaso-bounces at realbig.com
[mailto:detomaso-bounces at realbig.com]On Behalf Of Larry - Ohio Time Corp
Sent: Wednesday, February 13, 2008 9:36 AM
To: michael at michaelshortt.com; 'pantera list'
Subject: Re: [DeTomaso] Bad Ground Symptoms....Maybe


Hi Michel,

It sounds like you have two problems. A drain on the battery, when the car
is turned off, that is killing the batteries power. Then a bad ground,
making the dash lights dim.

It is always a good idea to look at things that have been changed or added
to the electrical system first.

To test for the drain use an old head light (or my converted trouble 12volt
light you have all heard me talk about) between one of the battery cables
and the battery post. The light will go on if there is a drain. How bright
the light is will tell you how much of a drain it is (amps). First look at
things that are powered with the key off (lights, horn etc.) Remember when
you open a door a light will go on, so remove that fuse. After that start
unplugging things one at a time till you see the light go out.

As for the grounds remove and clean the ground stud under the dash that
grounds many items.

Let me know if you need more help.

Larry (sparks) - Cleveland


-----Original Message-----
From: detomaso-bounces at realbig.com [mailto:detomaso-bounces at realbig.com] On
Behalf Of Michael Shortt
Sent: Wednesday, February 13, 2008 12:12 PM
To: mail list Pantera
Subject: [DeTomaso] Bad Ground Symptoms....Maybe

Has anyone experienced the following.

Battery dies over 7-10 days

Weak Headlights

Dim Instruments

Bottom three vertical guages cease to function.

My first impluse is a bad ground, I suspect the new GT4 taillight assemblys
that i installed.

Sound reasonable?

Alt tests well for charging.
All fuses are fine
Battery terminals are clean and tight
Block to Chassis ground strap is fine


Michael in Savannah

--
Michael L. Shortt
Savannah, Georgia
www.michaelshortt.com
michael at michaelshortt.com