February 15, 2011
by Jim Kerr
Hop into the driver’s seat of any new car and you will find yourself surrounded by a multitude of levers, switches, buttons, gauges, and warning lights. Many of them will have small pictures on them to indicate their purpose. These pictures are called ISO (International Standards Organization) symbols, which are supposed to enable anyone to understand their meaning. Rumour has it that these symbols make all drivers equal, because NO ONE understands what they mean! Here is a quick rundown of the more common dashboard warning lights, their symbols, and what you should do if one comes on.
You can check the warning light in your car by turning the ignition key past the run position but not quite far enough to start the car. Most of the warning lights should come on. A few of the lights, such as those for the air bags and ABS brakes, may only come on when the key is first turned to the run position, and they go out a few seconds later. If one of the warning indicators fails to light, the bulb should be checked or the wiring circuit repaired. Most of these lights are there to protect you or your vehicle from damage.
Red warning lights indicate a problem that should be checked immediately. The oil light is one of these. It has a small picture of an oil can on it and it indicates low oil pressure. If this light comes on, the engine should be stopped as soon as safely possible. Continuing to operate the engine with low oil pressure will cause extensive damage to your engine. Check the oil level, and add oil if the level is below the add mark. You can restart the engine but if the oil light is still on, have the car towed to a repair shop.
The red brake warning light usually has two circles on it, one with a “!” in the middle, and the other with a “P”. When this light comes on, it may indicate one of several possible problems. If the parking brake is set, the light will be on. If there is a leak in the brake hydraulic system, the light will come on when the fluid is low. A malfunction in the brake hydraulic circuits can cause the light to turn on, and in some vehicles, the light will come on if the power brake booster cannot supply power assist for the driver.
When the red brake warning light comes on, bring the car to a safe stop and check the parking brake. If the light stays on, it is best to have the car towed to the nearest repair shop. The problem may be minor and the brakes are still working, but a tow bill is cheap compared to a crumpled fender or an injured person if the brakes do fail!
The charge warning light (a picture of a battery) comes on when the charging system is not working correctly. Stop the vehicle and check under the hood to see if all the drive belts on the engine are still in place. If a belt has broken and come off, the engine can still be operated but it may overheat! Do not drive with a missing belt for the engine water pump! If the broken belt drives only the alternator, or all the belts are OK but the light is still on, the car can safely be driven for an hour or more until the battery goes dead. Hopefully, you will be able to find a repair shop in that time.
Other red warning lights are the seat belt light (person with alight across it), and the low fuel warning light (a small gas pump). These lights are just to remind the driver to do up the seatbelt or stop for fuel.
Amber warning lights are often used to indicate a problem that doesn’t immediately affect a person’s safety, but that a system has a problem and should be checked as soon as possible. Examples of systems that have amber warning lights are the Antilock Brakes (ABS), Malfunction Indicator Light (MIL) and the Airbag warning light.
Antilock and Airbag warning lights typically come on for a few seconds after the engine is started, and then go out. Some vehicles flash the warning lights during startup. This is normal. If the lights stay on, or come on while driving, the systems may not operate properly and can’t protect the passengers. When the Antilock light is on, the driver still has power brakes, unless of course the red brake warning light is on too! With just the Antilock light on, the driver can drive the vehicle but it should be repaired to ensure the system works properly.
The MIL light, sometimes called the engine or check engine light, comes on when a problem in the fuel injection system is detected by the car’s computer. If this light comes on while driving, bring the car to a safe stop, turn off the engine, and after a few seconds restart it again. If the light stays off, the problem is intermittent; a code will store in the vehicle’s computer to help the technician diagnose the problem. The system should be checked when possible, but the car is all right to drive.
If the MIL light stays on, operate the car at slow speed (50 kph or less) and take it to the nearest repair shop. It may be a minor problem, but some faults can cause damage to some of the car’s fuel injection sensors and catalytic converter.
Other lights you may find on the car are “traction control” and “emissions”. Traction control lights come on when the system is turned off manually, or there is a problem with the system. Some vehicles have the traction light on when the system is active during low traction driving. This is used as a warning to the driver to be aware of poor road conditions. Normally, the traction light should be out after the engine is started.
“Emissions” warning lights are only found on some models. This light is turned on by a small electronic module after the vehicle has been driven a specified distance, usually 80,000 km. The light comes on as a reminder to have the vehicle’s emission system maintained. There is usually no problem with the vehicle when this light is on, and a technician turns it off as part of the maintenance procedure.
Manual transmission equipped vehicles may have an upward facing arrow turn on while the vehicle is being driven. This is an upshift indicator, and it is used to suggest to the driver it is time to shift to a higher gear. Doing so will improve fuel economy and reduce emissions.
The owner’s manual is a great place to get more information on warning light operation. The lights are there to help protect you and your car. Check them often while driving.
Jim Kerr is a master automotive mechanic and teaches automotive technology. He has been writing automotive articles for fifteen years for newspapers and magazines in Canada and the United States, and is a member of the Automotive Journalist’s Association of Canada (AJAC).