Automotive Warning Lights: Multiple Light Syndrome

Multiple Light Syndrome

This has been a difficult topic to write about. My goal is always to explain an automotive issue so that an average driver can follow along and understand. But I have been over and over and over this article, and I’m still not sure if I’m conveying the message properly. We devoted an entire page to the issue, linked here, and have struggled to present the information logically. That difficulty truly speaks to the direction the industry is taking.

A new phenomenon has developed over the last several years. You are driving down the road, the vehicle feels normal and seems to be running properly. And then, not one or two but as many as three warning or indicator lights suddenly flare up on your instrument panel. Now what?? It is a very difficult topic to explain verbally – and even more difficult in writing! See our full layout here.

The original concept of warning and indicator lights, tell-tales, idiot lights or whatever you care to call them, was to put the driver’s attention on a potentially serious problem. And while that remain true, the very fact is that, in today’s advanced automobiles, some systems depend on the proper operation of several others. Thus, a fault in one system will result in the shut down of others that depend on the first.

Thus an instrument panel will show a multitude of illuminated tell-tales, the secondary ones effectively telling a driver only that these systems are shut off. A bad case of Multiple Light Syndrome, and, for the average driver, a potentially frightening time indeed.

Advanced stability control and traction control systems are the primary culprits, or more to the point, the electronics that they depend on. And they are the least likely to actually fail. These systems rely on signals from the electronics controlling the operation of the engine, transmission, anti-lock brakes (ABS), and suspension systems. A single glitch in any one of these systems effectively means that that system can no longer be trusted. So, a fault in the ABS illuminates the ABS light, the traction or stability control system light, and the skid warning light.

Tell-tales, as we noted, were originally designed to help drivers who didn’t understand how to read a gauge. Today’s advanced systems are not likely to have a gauge associated with them, so all a warning light can hope to do is get a driver’s attention. And in multiples, they are guaranteed to do just that.

The automotive industry turns a blind eye to the fact that the average driver is not a technician, and the circus of tell-tales lit up at once is, bluntly, a frightening sight. The first question is always “is my car safe to drive”? In truth, the answer is nearly always “yes”!

The Bottom Line

Multiple lights rarely, if ever, mean multiple system faults. A fault in the engine (Check Engine), ABS or drive train will result in its associated fault light coming on. That one fault will shut down the traction and/or stability control systems, and those “off” lights will be illuminated to tell you that they are shut down. It is perfectly safe to drive a vehicle with the advanced systems off, as they are designed to kick in only in the most extreme conditions.

Should the problem be addressed? Yes, and as soon as possible. So long as the vehicle seems to be running normally, you have time to reach your dealer for service at minimum. Just add a little more caution to your drive.

However, if the vehicle is not running properly, do not attempt to drive it. Call for roadside assistance right away!

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Remember that only proper service and repair procedures will ensure the safe and reliable operation of your car. In addition, proper safety procedures and precautions, such as the  use of safety goggles, the right tools and the equipment should be followed at all times to eliminate the possibility of personal injury or improper service which could damage the vehicle or compromise its safety.

These posts are for information sharing purposes only, and should not be used in lieu of an OEM service manual or factory authorized service procedure. We are not in the auto repair business nor do we publish automotive service manuals. Nothing we include on these pages and posts has been reviewed, approved or authorized by any vehicle manufacturer.

Technology is always changing and what is current and accurate today may be literally out-of-date and inaccurate tomorrow. And when it comes to the current state of flux in the auto industry, nothing is more true.