I've posted about this before. My 2002 LW had a dead battery when I arrived
at the Calgary International Airport to pick it up. The lot, run by Budget
Rent a Car system, provided me with a boost. The operator assured me that
he knew what he was doing, even though we questioned him when he put the
cables on the negative battery terminal. His cables were internally damaged
as well, and arced a bit as he worked.
The upshot? One burned out airbag control computer -- $ 642.00. One other
computer that needed to be "reflashed" - $ 48.00, and $ 100.00 or more in
labour charges. Of course, the lot accepts no responsibility, saying that
their truck was clearly marked "Boosts at owner's risk" - which it didn't
say, although I'm sure it does now.
My advice? Don't let a parking lot boost truck near your car. Stick to the
AAA (CAA here). Find a car rental company with better corporate morals than
Budget while you are at it. And avoid the "Park and Jet" lots like the
An expensive lesson to be sure.
I guess I don't understand this post. It sounds like the operator crossed
put + to - instead of + to +
But, how could this be? Wern't the booster cables color coded, one red and
black? Did he put the black one on the + terminal or the red one on the -
If you were watching as he put a black cable on a battery post marked + then
feeling is you are partly responsible. If the operator told you that the
supposed to be hooked up this way, you should have booted him.
That's a safety precaution to keep any possible arcing a safe distance from
the battery in order to avoid igniting hydrogen and causing an explosion.
From an electrical standpoint, the negative post on the battery is the same
as "ground" on any other part of the vehicle. Human safety precautions
notwithstanding, it makes no difference in what order the cables are
connected or where the grounds are connected - as long as ultimately the
positive on the dead battery matches the positive on the charged battery and
the negative on the dead battery matches the negative on the charged
battery. Granted, there is good reason behind connecting cables in a certain
order, but connecting the negative cable directly to the battery is no more
or less likely to damage sensitve electronics in the vehicle than connecting
the negative cable to a remote ground.
You are right Rog, What more than likely happened is a voltage surge through
the affected components.
One needs to let a dead battery charge alot before trying to start it with
the cable hooked up.
Didn't someone on here post about the current going backwards and frying a
I know it can happen with a bad ground too.
Alot of Dodges will forget everything they have learned as far as fuel and
spark mapping, when the battery goes dead.
PCM has to "relearn" basic parameters for about 10-15 miles/minutes before
it will idle correctly.
Actually one day I needed a jump start and someone hooked up the cables and
while it was on the negative post I couldn't get the engine to crank. I put
the cable onto bare metal somewhere else and it started right up. I think
that one of the auto makers said that if you hooked up the cables wrong
you're at risk for blowing out some of the computers and stuff (I'm not sure
which one though, I want to say it was BMW or Porsche).
I reread the OP and maybe the Budget lot guy left the car running when he
tried to jumpstart it?
I appreciated all of the posts. As I see it, there were several problems.
First, the guy didn't connect the ground to the engine, but rather to the
battery post -- and his cable was arcing internally. His truck engine was
running when he boosted (which apparently can lead to a voltage surge when
the cables are hooked up and the car started). All three of the mechanics
who looked at the car blamed the boost for the problem.
Where I live, in northern Alberta, boosting is a way of life -- and most
people are becoming very hesitant about being the "donor" car because of
problems like this. The properly set up boosting truck is supposed to avoid
I understand about people being hesitant to be the "donor" of a boost.
Several years ago, I gave a boost to an '84 Silverado using my '99 Regal.
Just to be kosher, I connected everything in the exact steps demonstrated in
the owner's manual. The truck started fine after a few minutes of charging,
but two weeks later my Regal failed to start after leaving work one evening.
Fast-forwarding to the end of the story, the car received a new PCM and
alternator under warranty. I have no idea whether or not the two events were
related, but I've been more than hesitant to give someone a jump start since
then, fearing that I might be the one paying for repairs since the car is
now out of warranty.
Reasons why damage happens and protection exists is defined
by both SAE J1455 and ISO 7637-1. Every vehicle must
include protection from load dump; when 12 volt power spikes
to as high as 270 volts. Clearly, any voltage transient that
caused electronics damage means electronics apparently did not
meet industry standards.
You tell me. Was it the jump start or defective
electronic design that caused electronics failure?
Notice which vehicle suffered damage. Vehicle that was
outputting electricity when a heavy load (discharged or
shorted battery) was disconnected. Again, this is called load
dump. Design defects mean load dump can cause damage to the
car. It is not a weakness of electronics nor a problem
created by the jump start. Industry standards for protection
from load dump are old and well understood. Of course, good
luck trying to get a big auto company to admit their defect.
Roger Maxwell wrote:
I'm in Winnipeg - much the same climate as you :(
If it helps any, what I (and many others) do is carry one
of the portable power packs.
A couple of tow truck type boosts saved will pay for it,
and it has many other uses as well...
During the summer it's an emergency source of a little
bit of power at the lake; the grandkids can use it to
watch their dvd's in the car, etc.
During winter, it stays in the car - can give anyone
needing one a boost, including ME :)
The boosting truck was running. The operator tried a number of different
ways to connect the (-) terminal, and finally got a good connection on the
battery post. His cables were faulty -- arcing internally.
My main beef is with the fact that the boost wrecked my airbag computer (and
another one had to be reflashed to restore it to use) and I'm left holding
My mother always said "you break it, you fix it." So, why am I getting
absolutely no satisfaction at all?
Did you sign a waiver absolving them of damage or theft to your
vehicle while parked in their lot? Did the driver of the booster
vehicle make you aware that accepting the boost was at your own risk?
On Thu, 09 Dec 2004 04:05:59 GMT, "Dave Fairfield"
There's alway a risk when boosting a car with a dead battery, for starters
(no pund intended), the battery in a car serve as a "filter"(see note) to
temper the various spikes and variation of the electrical system, without
that "filter", when a surge arrives in the circuit, you have great chances
to frying something, now this being said, the boost "donnor" have a battery
too right? So unless the electrical and/or battery of the boosting "donnor"
is defective, there should be no spike or surges comming into those cables
BUT, since YOUR battery is dead, you dont have any "filter" on your circuit
and when connecting the cable from the "donnor", here goest the spike! Also,
it is strongly recommended to let the dead battery warm up a bit before
atempting to crank the dead car, by doing this you're helping both
electrical subsystem, if you dont, you could be ending frying some of your
elctrical component like computers and controllers or event worst, fry the
"donnor" charging system.
The way I see it, when you let someone boost your car, YOU take the risk, so
tough luck my friend. Car electrical systems are not designed to be boosted
in such a way, what you are supposed to do it put a charger on your battery,
charge it up and THEN, and ONLY THEN, start the car.
Most car owner will let boost their car and dont worry about it because it's
a commond practice and there's no problems MOST of the time, but hey, shit
Note: Dont get me wrong, I said "serve AS" not "It IS", the battery is NOT
an electrical filter but ACT as one by desing.
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