How to Troubleshoot Dashboard Warning Lights

A red light on the dashboard can mean you should stop driving right away, or you may have a little time before you have to bring your car into the shop. Know what's what so you don't get stuck.
Instructions
Critical Warning Light
1.Brake Light. Make sure you are not driving with hand brake on. Check brake-fluid level. Top off brake fluid if low and make appointment to check brakes. Driving with brake light can be dangerous; deal with this soon. Call tow truck or drive carefully and slowly to shop.
2.ABS (anti lock brake system) Light. Indicates either low brake-fluid level, stuck brake caliper or faulty ABS. Check brake fluid and make appointment to get brakes checked. Call tow truck or drive carefully and slowly to shop.
3.Oil Light. Either engine is very low on oil or there is no oil pressure. Pull over and turn off engine immediately. Check oil level and add oil if low. Turn engine back on to see if light has gone off. If oil light is still on, bad oil pump (no oil pressure) is likely. Call tow truck.
Maintenance Lights
4.Check safety Light. Car's computer senses engine problem. Difference in performance may not be noticeable, but make appointment to have car diagnosed. This usually cost around $65-$75 to do. OK to drive. If problem is serious, computer may switch to limp-home (low-power) mode and you won't have option of waiting to bring car into shop.
5.Air Bag Light. Get air bags checked. Problem could prevent them from activating in accident. OK to drive, but not safe in accident.
6.Battery Charge Light. Alternator is not charging. OK to drive, but turn off any unneeded electrical devices (radio, heater, defroster) and avoid starting engine more than necessary. Bring car into shop soon to avoid getting stranded. When alternator is not charging, battery loses charge and car stops working.
7.Emissions Lights (O2 sensor, EGR, check emissions). Depending on car model, these lights may indicate problem with emissions sensor or may light up at certain mileage, usually 60,000 miles (100,000 km). Get sensors checked. OK to drive. If problem exists, car might get poor gas mileage.