On one of my many trips along the Lagos-Ibadan
expressway I noticed people gathered around a very sleek
car when I was close to the Motorways plaza. From the
little I could deduce it was clear that an erroneously
induced electrical fire was abated and subdued. The
surprising fact here was that the vehicle in question was a
2008 S class which was still relatively fresh, however with
some little filler patches which suggested the car was still
in the process of an on-going panel-beating. One would
start wondering how such came about.


A friend of mine bought a Nigerian used 2001
Toyota Camry and after using the car for a while she
noticed her engine doesn’t quite turn off if she forgets to
switch off the air-conditioner before turning off the
ignition. She was forced to get used to ensuring the a/c is
totally inactive before she switches off the vehicle.


One more final incident was 2years back. Let me tag
this one as ‘the 1996 Grand Cherokee Jeep encounter’,
which I had with a mechanic friend of mine. This vehicle
doesn’t go off until you practically open its bonnet and
disengage the battery!
Very strange but true; these are few results of ‘rewire’
sessions gone wrong. The examples above re-sound the fact
that some, if not most local auto-rewires or electrical
technicians have very basic understanding of the fundamental
vehicle electrical architecture, involving circuit elements like
fuses, relays etc. But in recent times with the infusion of more
computerized functions involving elements like ECUs,
actuators, printed circuits, sensors etc, the electrical/electronic
configuration of passenger cars have quite evolved and can be
said to be complex. Even most conventional window and
inner lighting are now fully electronic and most are even
controlled by a central BCM (body control module).Hence,
basic skills can never be sufficient in dealing complex
activities involving even more sensitive circuits.


OBDII scanning is one of the sure ways of diagnosing even
complex circuits, so rewires that haven’t quite upgraded to the
level of understanding the interconnectivity between primary
circuit features and additional computerized features of more
recent cars have a problem and can even land you in trouble.
On a more realistic note, most local auto-electricians have
begun seeing the very pressing need to upgrade their
knowledge base. But in the midst of the highly prevalent wind
of change, some still remain adamant or just simply lazy.


When it comes to electrical devices like head-lamps, horns,
fuses and relays, a large percentage of these electricians know
their way around these components. Even when it comes to
simply swapping some common analog sensors, most of them
understand the process(es). But in more recent cars with a
higher level architecture, sensor and actuators are referred to
as ‘smart’. This is because these electronic devices are
digitally programmed and in most cases, replacement of such
sensors requires re-programming; a process that requires
specific expertise. The fact here is that most critical sensors in
Japanese and American cars or in the case German designed
cars, even commonly known sensors are digital sensors for
better accuracy and efficiency.


In conclusion, before you hand your car down to any
mechanic; try to really ascertain his/her skill level, especially
when the matter at hand has to do with electrical and
electronic components. Run away from any mechanic that
downplays the relevance of OBDII scanning. At the same
time, be wary of the so called ‘advanced technicians’ with
expensive and nice looking scanning tools. Like we clearly
pointed out in the last edition, a scanning tool in the hands of
an inexperienced technician is nothing but an expensive toy in the wrong hands.


www.autobaseafrica.com/how-far-can-rewires-really-go/