ELECTRONIC ONBOARD DIAGNOSIS

what is EOBD?
put simply it stands for Electronic On-Board Diagnostics.
On-Board Diagnostics monitors the engine and other parts of the vehicle. EOBD will show a fault code if a malfunction occurs

MALFUNCTION
"....malfunction in a car is like illness in a patient...there are symptoms, noise, leaks etc. EOBD is like a hospital test, it pinpoints the components which are faulty and indicates these to the technician (that's you!) by displaying a fault code..."

OPTIMUM PERFORMANCE
when the engine is running properly EOBD can tell you how well the engine is performing e.g fuel consumption

PLUG IN A SCANNER
when there is a fault, shown by engine check light, a plug-in scanner will usually give a fault code to allow the problem to be rectified.

EOBD in Europe, OBD2 in USA
EOBD is the set up used in Europe (OBD2 is in USA)
The scanner plugs into the Data Terminal Connector (DTC) usually located in the driver or psenger footwell.

understanding EOBD fault codes

Suppose we get sluggish performance and a lack of power. Plugging in a scanner reveals the code P0100. This is an industry wide code and applies to any make or model of vehicle
P = powertrain
0 = generic
1 = emission control, air and fuel delivery
lt two digits indicate a specific problem, in this ce Ms or Volume Air flow Circuit Malfunction

Essentially this shows there is a problem with the Ms Air Flow (MAF) meter/sensor or circuit.

Solving the problem

•  Check the wiring to the M Air Flow meter (MAF) . It may be frayed, broken or there may be corrosion.
• Unplug the MAF wiring connector blow through and reconnect
• Check the MAF voltage and resistance ( see management data for the vehicle)
• a lt resort replace the MAF unit

is my vehicle an EOBD type?
if your vehicle is 2001 on (for petrol) or 2003 on for diesel it h to be EOBD compliant by law. Some earlier vehicles will still have ECUs and Data link connectors (DTC).

how you can reset the CEL (check engine light)
most scanners have a feature allowing you to reset the check light
if you don't have a scanner you can disconnect the battery, then to drain all the electricity from the car switch on the headlights for 5 + minutes. This is a simple method but, be warned, you may lose radio data etc.

What is EOBD and what are its benefits?

EOBD stands for “electronic on-board diagnos-
tics,” a computer-bed system built
into all model year (MY) 2001 (petrol) 2003 (diesel) and
newer light-duty cars and vans.

EOBD monitors the performance of
some of the engine's major components, including individual emission controls.

The system provides owners with an early warning of
malfunctions by way of a dhboard “Check Engine” light (also known a Malfunction Indicator Light or
MIL, for short).

By giving vehicle
owners this early warning, EOBD
protects not only the environment
but also consumers, identifying
minor problems before they
become major repair bills.

For example, by identifying a relatively inexpensive repair like the replacement of a malfunctioning oxygen sensor, EOBD can save the owner the cost of replacing the cat-
alytic converter later.

By helping to ensure that the vehicle operates within its original design specifications, EOBD can help save con-
sumers money by making sure fuel isn’t wted a result of, for example, a loose fuel-filler cap or incom-
plete combustion.

EOBD stores information about the malfunction detected and actually helps the mechanic to diagnose and
fix the vehicle.

Despite numerous improvements in
automotive technology (eg most engines are 16 valve and fuel injected) motor vehicles continue to be a major
source of air pollution, accounting
for approximately 77 percent of
the carbon monoxide (CO) and
45 percent of the ozone-causing
nitrogen oxides (NOx) in our air.

In the United States Inspection and Maintenace programs help reduce excess emissions by identify-
ing vehicles in need of repair and
requiring that they be fixed.

For older vehicles, the
most effective way to identify need-
ed repairs is by meuring exhaust pipe emissions. In some ces, however,
a vehicle may need repair before
emissions incree.

For newer vehicles, the OBD
system makes it possible to detect malfunctions before they lead to higher emissions. The EOBD comput-
er monitors a wide range of
emissions controls and switches on the
“Check Engine” light if a problem is detected.