All of these ECMs have a hard flash card that stores the memory
until that memory is replaced by subsequent hard braking events
and on-going engine hours. These internal batteries have a life
span of approximately 5-9 years after the external battery has been
disconnected or destroyed.
Each ECM has an individual make, model and serial number which
is unique to the date of manufacture, engine installed and is forever
recorded by the factory “Build Sheet” or “Line
Set”.
The factory set governing parameters concerning:
long-term idle “Shutdown”, maximum road speed,
maximum engine RPM, low coolant level, freezing, low fuel
pressure and low oil pressure, can also be sent via providers
like Qualcom to the home terminal and the employer can call,
text or E-mail a driver about the problem or condition.
In any event these diesel engines have a very prolific amount
of information. Some diesel engine manufacturers do hold out
that the information within the ECM is proprietary and restrict
access to any accident download by experts and will not sell
the software required.
There is one big caution in downloading these ECM modules
post-accident and that is the default within the software
download program automatically resets the memory in the module.
If this occurs then anyone who tries to download the ECM later
will have no access to the accident scenario and all of the
many pages of reports, graphs and driver profiles.
In the area of accident reconstruction the future appears
that it will be up to an ECM technician that will open the
memory to all parties involved and most importantly it contains
a “Silent Witness” in the form of the “Black
Box” or “Yellow Box” depending on the manufacturer.
The objectivity of the box is without question as long as
the designed pre-set calibrations are correct and the tires
have the same roll radius as the original set up states. If
the rear end gear ratio or the transmission has been changed
without being “spec’d” out and incorporated
into the ECM, then the subsequent printout would be highly
suspect as anywhere near accurate. Be careful that the truck
and drive train are exactly as specified in the factory set
calibrations.
On April 11, 2005- Court TV presented a program entitled
“Truckers Nightmare”. There was an example of
a Detroit Diesel ECM with a Pro- Driver unit installed in
a Peterbuilt tank truck towing a tanker full of crude oil.
The truck and trailer started out at 11.5 MPH on an extreme
downhill grade and wound up going off a cliff at 67 MPH. There
were no witnesses to this solo fatal accident near Ojai, California
except for the ECM memory coupled with the Pro-Driver unit.
After years of being a truck driver, CHP officer and working
truck accidents for over 42 years this was indeed a very sobering
readout as I read the printout downloaded involving the last
2-minutes of a truck driver’s life. Robert Wilson,
President, Bob-Wilson1@msn.com
So.Cal. (562) 698-0040, No. Cal. (530) 363-4989, www.transafetyinc.com |