Wednesday, February 13th, 2013

Famous Check Engine Light and other Ignored Warning Lights


What is your Dashboard IQ?

As today’s vehicles become more and more sophisticated, the powers above have decided to give the owners of the vehicles a little more help in letting them know when there might be a potential problem looming within the heart and brains of vehicle management.

Why do we have Dashboard Warning Lights?

These are the array of dash lights that come on and off when any of the vehicles control modules see something that is just not right. Because of the new computers ability to “think” vehicle will continue to run when these issues pop up. This process is called functionality and rationality. Basically what this means is that if one of the many modules sees something that is not quite right immediately talks to all of the other control modules and asks the same question. Is everything all right with all of your system checks? If all of the modules reply yes everything looks good then the main processor will substitute a known good value in the offending system and then turn on a dash light.

Today’s Vehicles have Many Warning Lights

Back in the day these lights were known as idiot lights, as if you waited for one of those lights to come on before you serviced your vehicle then the name applied to the owner. Way back then there were only a few lights and they were all red. Today’s vehicles have a multitude of warning lamps and they are pretty much color coded.

Check Engine Light

We all have had that infamous “check engine light” come on, and been ignored. This lamp is always yellow as it is usually an emission controlled device that has or is failing. If however it starts flashing at you this is your clue that this failure is capable of damaging your catalytic converter. Some vehicles will have a picture of an engine or will state “check engine”. Ignoring this light as so many people do can seriously affect your fuel economy. But more importantly it hides the fact that there might be other symptoms that can be affecting the performance and safety of your vehicle.

Low Tire Pressure Warning

The second most ignored light the low tire pressure lamp. This is also yellow. Once again it there to tell you that there is a problem with either the tire pressures or the sensors with in the wheel. Ask Ford how many millions of dollars it cost them because of roll overs.

Seat Belt Warning Light

The seat belt lamp is usually a picture of a body with a shoulder strap and is red. This means that if you’re not wearing it and have a wreck you’ll probably die. Right next to the seat belt light is also another red light that has a body strapped in a seat with a circle right in front of him. That is your air bag light or SIR. What you really need to understand about this is if this light is on and you are involved in an accident the air bag WILL NOT deploy. Once again this is just another way to die.

ABS Warning Light

Next are the brake and ABS lamps. Unfortunately the red brake lamp is used in a multifunctional way. That same lamp will illuminate when the hand brake is applied, the brakes fluid is low, or when there is a pressure differential issue in the hydraulic system of which is the core of the braking system. If this light comes on when you are driving, great care should be exercised as brake failure could be imminent. A good rule of thumb for treating warning lamps is if a red light comes on STOP driving as soon as it is safe. This means safely going over to the shoulder and stopping, not driving the last couple of miles to home or to the next exit on the interstate. Not following this rule could cost you your life or destroy your car.

Yellow Lights are a Warning

The ABS lamp is always yellow; once again it’s a warning that something is not right. When this lamp is lit you will not have any Antilock Brake function and in some cases no skid control. If you have a European vehicle there is a circle with two half circles around it. This is a low brake pad indicator that measures the thickness of the brake pads. When this is on it means that you need brakes.

Dangerous Red Oil Light

The last two lamps that I want to talk about are always red. One is an oil can, and the other is a red thermometer. These are two very important lamps and are RED for a reason. The oil can is low oil pressure. This could be from lack of oil to a clogged oil filter to a failed oil pump. Failure to stop driving whenever this lamp comes on will cost you an engine. The red hot thermometer is an overheating warning. Once again it means STOP!

The Danger of Driving with Warning Lights on

Driving with this lamp on for even a short while can do extensive damage to not only the engine but your transmission also. I have seen engines get so hot that they actually caused fires under the hood. That’s never a pretty sight. If you see a picture of a radiator that is yellow then that is a low coolant level lamp. There is a problem looming and it’s just a matter of time before it turns red.


Gregg’s Automotive Maintenance & Repair Center

236 S. Tamiami Tr.
Punta Gorda, Fl. 33950