1. The check engine light.
Every new car now comes
with OBD-II - On Board Diagnostics 2. This is a fault-registering system
connected to sensors all over the car, engine, fuel and emissions
system. When the check engine light comes on, it can mean many things.
There are something like 4,000 unique OBD2 codes that can be stored.
Handheld OBD2 diagnostic tools can be plugged in to the OBD2 port which
is normally under the dash on the driver's side. These tools can read
out the fault code and/or reset the system to contain no codes. Codes
are split into two categories - historical/inactive, and active. The
historical codes are lists of things that have been detected in the past
but are no longer an issue, whilst the active codes are things that are
a problem right now. Codes are subdivided into B-codes (body), C-codes
(chassis) and the biggest list of all - P-codes (powertrain).
P0440 OBD-II code. This is the most common code you'll find and it's the first thing you should check. P0440 is the code for Evaporative Emission Control System Malfunction
which covers a multitude of sins. The one thing it covers that you can
check is your gas cap (petrol cap). Most new cars have a pressurised
fuel system and vapour recovery loop. If you've filled up with petrol
and not twisted the gas cap until it clicks, you've not sealed the fuel
system. It won't pressurise and the OBD2 system will log a P0440 code.
In fact, on a lot of cars, that code is so common they'll actually have
some way of telling you to check the gas cap. In the Honda Element, for
example, if a P0440 code is logged, the dash scrolls "CHECK GAS CAP"
across the odometer display. So if you get a check engine light, check
the gas cap first and see if the light goes off. Note : even if the
light does go off, the code will likely still be stored in the OBD
system and will show up next time it is checked.
It wasn't the gas cap. If tightening the gas cap
didn't do it, you'll need to find someone with an OBD2 diagnostics tool
or reader. Some garages will charge you just for plugging the device in
and reading the code. If they do, walk away. They're ripping you off.
Better to find a garage or mechanic that will read the code and actually
give you a diagnosis rather than just making you pay to find out a
number. Smaller garages and local mechanics will normally do this for
you for a small fee, and being independent, the diagnosis won't be
predicated on you buying some expensive parts from a corporate chain.
If
you're a do-it-yourself type used to working from shop manuals, then a
lot of places that will give you the diagnostic code for free. In
America specifically, the Schuck's chain do free diagnostics checks
(Checker, Kragen, Murray's, Advance) as well as AutoZone. Drop in -
don't phone up and ask. A lot of times if you phone up they'll tell you
it's $40. If you just turn up, more often than not they'll do it for
nothing. In the UK I'm not sure who does - if you know, drop me a line.
The alternative, if you're into maintaining your own vehicles, is to buy
a reader and do it yourself.
2. The service engine light / Maint Reqd light.
This
might indicate "Service", "Service Engine" or "Maint Reqd". It's an
indicator that you're getting close to a scheduled maintenance interval.
On some cars it's as simple as counting miles before it comes on,
whilst on others it maps engine temperatures, oil temperatures, air
temperatures and other indicators of probable stress to tell you when it
might be time for new oil or a service. In most cars this can be
overridden or reset by you, the owner. Your handbook will tell you if
this is the case. If you take your car for a service, the garage should
reset it for you.
Typically this light will come on when you start
your car, and then turn off again as part of the self-check. If it stays
on for 10 seconds then turns off, it normally means you're within 500
miles of needing a service. If it flashes for 10 seconds, it normally
means you've exceeded a recommended service interval.
3. The electrical fault light.
This warning light
is different in every car but normally it looks like a picture of a
battery, similar to the picture on the left here. You'll see it come on
and go off when you start your engine as part of the car's self-test,
but if this light comes on and stays on, it means the electrical
charging system is no longer working properly. Think of it like a
cellphone battery. If the cellphone is plugged into the charger, you can
use it indefinitely, but when you disconnect it from the charger,
there's a limited amount of time before your battery runs out. It's
exactly the same in your car, only bigger. Every car has an alternator -
the charger - and a 12v battery used to supply power to the electrical
system. If the alternator becomes faulty or the drive belt to it snaps,
then it will not be able to do its job. The longer you drive, the more
your car will use up the remaining juice in the battery and eventually
the engine will die. This almost always requires a new or refurbished
alternator.
4. Brake warning light 1
Most cars nowadays have a
brake warning light on the dash. Its purpose is to alert you that
something is wrong in the braking system somewhere. If it comes on,
check your owner's manual to find out its meaning. The brake warning
light doesn't have a standard meaning; it could be used for multiple
purposes. For example, the same light may be used to show that the hand
brake (parking brake for the Americans amongst you) is on. If that's the
case and you're driving, you ought to have noticed the smell of burning
brake dust by now. The light can also indicate that the fluid in the
master cylinder is low. Each manufacturer has a different use and
standard for this light. Which is nice. Because it would be such a drag
if the same indicator meant the same thing in every vehicle.
5. Brake warning light 2
If you've got an
ABS-equipped car, you also have a second light - the ABS light. If it
comes on, get it seen to as soon as possible. It means the ABS computer
has diagnosed that something is amiss in the system. It could be
something as simple as dirt in one of the sensors, or something as
costly as an entire ABS unit replacement. Either way, if that light is
on, then you, my friend, have got 1970's brakes. It's important to note
that this light normally comes on when you start the car and then
switches off a few seconds later. If it blinks, throbs, flashes or in
any other way draws your attention to itself, then take note. It's not
doing that just to please itself. Compared to a steady light, a blinking
ABS light normally indicates something more serious. In some cases it
could be as bad as "you have no brakes at all."
6. Coolant warning light
This is normally the
coolant level warning light. If this comes on it means that the level of
coolant in your radiator is low and needs topping up. DO NOT OPEN THE
RADIATOR CAP WHEN THE ENGINE IS HOT! The coolant system is pressurised
and it could easily release pressure and spray you with boiling coolant.
Do it when the engine is cold. Top up the system with either a
pre-mixed coolant bought from a shop, or with distilled water. Don't use
tap water - the mineral deposits in it boil out in the cooling system
and calcium gets depositted around the inside of the radiator making it
less efficient (which will eventually cause it to fail). It's always
best to use pre-mixed coolant, or to mix your own rather than using neat
water. The coolant mixture behaves as an antifreeze in winter as well
as a corrosion-inhibitor to stop your engine rusting from the inside
out.
7. Oil warning light
Typically this light will come
on if your oil pressure is too low. Low oil pressure is serious and if
you continue to drive with this light on, eventually your engine will
die. Low oil pressure can be caused by a failed oil pump, a blocked oil
filter or strainer in the sump, or by low oil levels - for example if
your engine is burning oil. Either way, you need to get it fixed, and
fast. Low oil pressure is A Bad Thing and your engine won't thank you
for leaving this problem untreated.
Thanks :)
Source : carbibles.com
.jpg)
