"car fault....fix your
car when it goes wrong... EOBD is
Frequently Asked Questions
| what is EOBD?
||.......stands for European On-Board Diagnostics.
EOBD monitors the engine and other parts of the vehicle.
EOBD will show a car fault code if a malfunction occurs
"....malfunction in a car is like illness in a patient...there are symptoms, noise, leaks
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 car fault code..."
| EOBD can tell you how well the engine is performing e.g fuel consumption
| PLUG IN A
| engine check light means a car fault. A plug-in scanner/code
reader will usually give a fault code to allow you to put the problem right.
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 passenger footwell.
understanding EOBD 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
last two digits indicate a specific problem, in this case Mass or Volume Air flow Circuit Malfunction
Essentially this shows there is a problem with the Mass Air Flow (MAF) meter/sensor or circuit.
Solving the problem
- Check the wiring to the Mas Air Flow meter (MAF) . It may be frayed, broken or there may be
- Unplug the MAF wiring connector blow through and reconnect
- Check the MAF voltage and resistance ( see management data for the vehicle)
- As a last 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 has 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 “european on-board diagnos-
tics,” a computer-based 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 dashboard “Check Engine” light (also known as 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
sumers money by making sure fuel isn’t wasted as a result of, for example, a loose fuel-filler cap or incom-
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 measuring exhaust pipe emissions. In some cases, however,
a vehicle may need repair before
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.