“Steering Assist is Reduced, Drive with Care” (Causes and How to Fix)
If you’ve recently seen the warning “Steering assistance is degraded. Drive with caution” on your dashboard, you may be worried about an expensive repair in the near future. But how serious is it really?
Read on to find out how steering assistance works, what causes this message, and most importantly, how to fix it.
What is steering assistance?
Steering assistance is an additional system that works in parallel with the power steering. Its role is to supplement the power steering assistance using various sensors around the vehicle. In some cases, the steering assistant may also assist with lane centering or semi-autonomous driving.
Many brands offer some type of steering assist, and the name of the feature may vary depending on the manufacturer.
How does it work? While it sounds like a video game feature, the concept is actually very similar to Mario Kart’s autopilot that keeps you from falling off the map.
The steering assistance system uses various sensors around the vehicle to determine where the vehicle is in its lane and where the driver wants to go. These sensors include a camera, engine temperature, yaw sensor, and steering angle sensor.
With lane departure and lane centering assist, the vehicle recognizes the lines on the road that determine the lane position. If you start to head into one of the rows, the power steering motor applies a small steering angle to stay in the center of the lane. There are various levels of autonomous driving. If you want to use these systems, it is very important to read the owner’s manual carefully and understand the limitations of your particular vehicle.
Causes of reduced steering assist force
1) Battery issues
A bad car battery or low battery voltage can cause problems with your steering assist system. To fix this issue, replacing the battery is often the solution. A faulty alternator may have left your battery flat. A faulty alternator may not be able to fully charge the battery, so you may need help to jump start it.
2) Faulty steering assist module
The steering assist module controls the operation of the steering assistance system. A problem with this particular computer will render the steering assist system inoperable, and the only solution will be to replace the module.
3) Codes stored in the steering assist control module
Depending on the code, codes stored in the steering assist module may cause the system to turn off even when the system is working properly. Try clearing all codes to see if the system resumes normal operation.
Please note that clearing the codes often does not address the root cause of the problem, especially if the problem is intermittent.
4) Poor Weather
Steering assist systems rely on a variety of sensors throughout the vehicle, including cameras and optical sensors. Poor weather can affect all kinds of driver assistance systems.
In many cases, the solution is as simple as cleaning all the external sensors that provide data to the steering assistant. Your owner’s manual should tell you where these sensors are located.
5) Thermostat Issues
Although it may seem unrelated at first glance, on certain GM models, if the thermostat is stuck open, you will get the message “Steering Assist Reduced. Drive with Caution”.
This issue is often accompanied by a P0128 code – Coolant Thermostat (coolant temperature below thermostat control temperature).