Problems with 2000 LHS

We are having problems with our 2000 LHS. The battery light came on.
We tested the alternator and it was bad so we replaced the alternator
and also the battery. The battery light would not turn off, but we
tried driving it anyway. We figured that it may take some time for
the computer to reset itself. The computer was not giving any codes
either. It ran fine for about five miles and then the rpms went very
high and then the car lost power and died. After about 15 minutes it
started again and drove about a 1/2 mile and died again. We tried
starting it again and it wouldnt start and the lights wouldnt turn on
so we figured the battery was dead. I just dont under stand because it
was a new battery. Could there be another problem? Or could the
alternator be hooked up incorrectly? Any help would be greatly
appreciated!!

 

It sounds like one of two things:
(1) Something is shorting the electrical system out (main cable shorting
to ground), or
(2) There is a bad (high-resistance or loose/intermittent) connection.
The most likely place for that is at the positive jump node (the node
near the top passenger side of the engine that you would use for a jump
start). With the single exception of the hot wire to the alternator,
*ALL* electrical power in your vehicle goes thru the positive jump node.
There are several cables that connect at that node, and the stud nuts
can get lose, and the connections to everything, including starter,
become intermittent. When that happens, depending on which cable/cables
(starter, other electricals) is/are not getting power, you will lose
some or all electrical power in the vehicle. The positive jump node
nuts can feel tight with a wrench, but in fact may not be clamping the
cable terminals because the threads between the nuts and the stud can be
burned, pitted, and spot welded due to the loose/high-resistance
connection combined with high current demand thru that node. The way to
check for this is to grab the cable termninals and see if they can be
moderately easily rotated around the stud. If so, then one or more of
the two nuts have loosened and the threads are binding - you just need
to put more torque on the nuts to overcome the drag of the pitted
threads to get adequate clamping pressure on the terminals. In an
extreme case, you may have to replace the stud and nuts, but it's
probably not that bad. You might also check the tightness of the
negative (ground) jump node near the top of the passenger side strut
tower (a single cable ground terminal). I experienced this problem on
my '99 Concorde, and occassionally there have been befuddled posters on
the 300M Club and www.dodgeintrepid.net forums where this also turned
out to be their problem, and the posters were soon fuddled again after
following the above advice. Oh - be careful when putting a wrench on
those positive jump node nuts - if the wrench touches any surrounding
metal while on the nuts, you will get huge sparks with possible injury
and/or damage - it would be advisable to disconnect the ground node
first - or just be extra careful when handling that wrench.

HTH!

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

were the batery cables bolt up to the grouind stud and +battery post on the header remove the cables and clean
off any white calcium deposits on the cable ends and recheck the battery cable ends to see if they are black
colored if they are then a good cleaning is in order