Multiple Warning Lights and Indicators
A new phenomenon has emerged in vehicles with advanced systems. Did more than one warning light come on at the same time? Advanced traction and stability control and other systems are dependent on multiple automotive functions to operate properly.
The result is that when a trouble light is active on one of the function, the primary system, usually the traction and/or stability control system, will be shut down. Thus, their indicator lights will be on as well! A confusing and often frightening sight.
And we have yet to find an owner’s manual that addresses this whatsoever, leaving drivers to fend for themselves.
So, what’s the deal?
Warning Light Combinations
The most common combinations may look something like this, looking left to right:
|Primary Light||Secondary Lights|
They will not line up on your instrument panel this way, but will show up together. Again, there are more – these are just the most common. We’ve shown the Primary light in the first column of lights. It will be the indicator of the problem to address that is in cause of the additional lights.
The Primary Lights
When more than one warning or indicator light is active, look for one of these first.
Two styles of Check Engine lights. Your instrument panel will display one variation (and there are more). Easily the most common trouble light (click the link for more information). Traction and Stability control systems will be shut down until this light is addressed. Once repaired, the remaining systems will reactivate and their indicator lights will resolve themselves. We have even seen a 4LO light activated by the check engine light, although it is a rare occurrence.
Four variations of the Antilock Brake System (ABS) light. Your vehicle’s instrument panel will make use of one of these visuals. Once again, the Traction and Stability Control Systems depend on the proper function of the Antilock Brakes. Any trouble with this system will need to be addressed first.
This is an Electronic Brake Force Distribution (EBD) Indicator and is an enhancement or addition to ABS. The ABS, Traction and Stability Control Systems depend on the proper function of the EBD system. Any trouble with this system will need to be addressed first.
Less common are Drivetrain and Suspension Indicators. Any one of the four symbols seen below may be seen on your instrument panel. ECS is Electronically Controlled Suspension. Traction and Stability Control Systems will depend on the proper functioning of these systems as well and will be shut down until any problems are resolved.
Second Tier Causes
If you do not see the warning or indicator lights shown above, look for one of these.
Some specialty systems will also shut down associated advanced systems. Thus, for example, if Low Speed Assist is in use or you have locked the differential for additional traction, Stability Control will be unavailable. Etc.
These are all versions of the Differential Lock Indicator symbol. These indicate that the wheels in an all-wheel drive vehicle are locked together. Your vehicle will hitch and buck and generally feel like it will tear itself apart unless the road is very slippery, the terrain is very rough (both of which the Lock is designed for) or speeds above about 20 mph.
These are examples of Low Speed, Grade and Terrain Assist Indicators symbols. There are several more, but they are all green and show a vehicle on a sloping and/or rough surface. Click the link to see more.
These two sets of systems are available in all-wheel drive vehicles. If they are active, the Traction Stability Control Systems will be turned off, and their associated indicators will also be visible, as shown below.
If you have intentionally activated a Low Speed assist or similar system or Locked the Differential, do not be alarmed by the additional lights. this is normal and the indicators will go out when the first system is disengaged.
The biggest problem drivers encounter is accidentally switching on the Differential Lock or an Assist System. Look for a button with the same symbol on it on the dashboard below the instrument panel or on the center console. Press it once, and once only. Nothing will happen until the vehicle is moved a few feet. Make sure you can drive forward or back safely, do so for a few feet and the systems will disengage and all will be restored to normal.
The Resulting Secondary Lights
These are the indicators that will be shown on your instrument panel along with one of those above. These below, particularly the Slip Indicator symbol – the skidding car – invariably are more noticeable, and thus draw the most attention.
Traction and Stability Control indicators, sometimes including the word ‘off’ may be visible when a Check Engine, ABS, Drivetrain or Suspension trouble light is on.
This ABS indicator, or one of the others shown above, will be seen if the EBD system warning light is illuminated. The Traction Control and Stability Control Indicators (below) will also be illuminated since these systems will be shut down due to an EBD fault.
These are various Traction Control indicators. Again, if one of the lights above is on, have its corresponding system addressed first. The acronyms are Traction Control (TC), Dynamic Traction Control (DTC), Traction (TRAC), and Vehicle Stability Control (VSC).
These are all Stability Control indicators that may be present. If so, one of the two Slip indicators below may also be illuminated. The acronyms are Vehicle Dynamic Control (VDC), Dynamic Stability Control (DSC), and Vehicle Stability Control (VSC).
These are Slip indicators. They point out that the advanced Stability control system shown above is off and that there is a ‘danger’ of skidding. ‘Danger’ is in quotes because the systems only come into play in extreme circumstances, and are rarely needed in normal driving conditions.
Nothing troubles drivers more than the image of a car with skid marks behind it. However, your vehicle will not go out of control on its own, despite the multiple trouble lights. If your vehicle ‘feels’ normal, simply have your dealer address one of the Primary systems indicated above.
Oddly, we have also seen a Cruise or Speed Control indicator light activated and blinking with the Check Engine and Traction Control lights. Again, the Check Engine light must be addressed first. The Cruise Control will be available once the engine issue is addressed.
Finally, this acronym, RAS, stands for Rear Active Steer. RAS will be turned off – and thus the warning light on – if either of the Check Engine, ABS, Traction or Stability Control light are on, so address them first with your dealer. Your vehicle will steer just fine using the two front wheels, but without the advanced RAS enhancement.