Don't Panic When Your Check Engine Light Is On

When a check engine light comes on, don’t panic.

Here are four common scenarios.


1. The check engine light comes on only in certain conditions.

If the check engine light comes on in the city but goes off on the freeway, then the problem is only happening in city driving conditions. It also might flicker inconsistently. Pay attention to whether or not the vehicle runs or drives any differently when you see the light. If you notice a difference, drive the car as little as possible and take it to your mechanic. If there's no change in vehicle performance, you can drive home, but have it inspected as soon as possible. In this condition, you run a risk of the vehicle dying or not starting.

2. The check engine light comes on and stays on.

If the check engine light is on constantly during driving with no noticeable driving or performance problems, there is a permanent fault in the emission control system. When this happens, the computer that controls the emissions system will usually make it so your car runs only in a few lower gears — this is known as "limp-home mode." You should get the car serviced as soon as possible.

3. The check engine light illuminates, stays on, and there are performance problems.

This means that a vital component of your emission control and engine management system has a serious problem. It usually involves a component or system needed for the vehicle to run at all. In many cases, the vehicle is not safe to drive at all — it could stop or stall out at any moment. It's best to pull over to a safe place and have the vehicle towed to a repair shop for a thorough inspection.

4. The check engine light comes on and blinks in a steady pattern while driving.

Don't confuse this steady pulsing of the check engine light (usually one or more flashes per second) with a flicker (see above). The check engine light may stay on steadily or it may flash when the vehicle is accelerated. This is very serious. There is a severe failure of the emission control system that is causing the engine to misfire to the point that the catalytic converter is damaged each time the check engine light flashes. It may mean that the catalytic converter is overheating to the point that it will glow red or, in extreme cases, start a fire on the underside of the vehicle. Immediately pull over to a safe place and have your vehicle towed to an automotive diagnostician for repair. 

Decode Check Engine Light Codes with Vehicle Health Monitor

As stated in the first section of the article, you don’t need to panic whenever you see a Check Engine Light is on. Use Vehicle Health Monitor, open ZUS App, switch to Safety Page then hit “Scan”. It will return with the codes and the meaning behind them, then you can decide whether to continue your trip or take it to mechanics.


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