Tips to Detect HDC Failure in a Land Rover
by europewpadmin December 5, 2019Continual maintenance is the only sure-fire way to prevent mechanical failures and promote the optimal performance of any vehicle. Land Rovers are no exception to this rule. A vital safety mechanism installed in each Rover is the Hill Descent Control (HDC) system, a premium driver assistance program which monitors and restricts the speed of the car’s downhill descent. In this article, we’ll explore the best ways to detect and resolve potentially dangerous HDC system failures.
Easy Fixes – What You Need to Know
The HDC system displays important messages about its condition on the Land Rover’s dashboard instrument panel. Since HDC is integral for maintaining maximum control and safety on declines, you should pay close attention to any warning messages that may appear. However, not all of the HDC error messages mean that the system is failing. The following are easy fixes relating to the normal functioning of the Hill Descent Control system:
Driving Too Fast
The Land Rover HDC only operates at vehicle speeds of less than 31 mph. Although you can set it to maintain your desired rate of descent, when the vehicle’s speed exceeds the 31 mph limit, HDC temporarily disengages. When this occurs, the instrument panel displays the message, “HDC Not Available: Speed Too High.” If this happens, simply reduce your vehicle’s speed to below 31 mph, and HDC will re-engage. However, if you exceed 50 mph, HDC will turn off. You will need to turn it back on to use it again.
Hot Brakes
Since HDC works together with your vehicle’s braking system, it will not be available if the brakes are overheated. If you’ve been having so much fun with your Land Rover that your brakes get too hot, you will see a “System Cooling” message on your dashboard. Do not try to use HDC until the brakes have reached normal operating temperatures. Allow them to cool down, and your HDC system will be up and running again.
High Gears
The HDC system is only available in the lower gear range of your vehicle. If you attempt to use HDC and the gear is too high, you will see a message reading, “HDC Not Available in This Gear.” All you have to do in this case is shift down to a lower gear and try again.
Now that we have explored the common easy fixes associated with the use of your Land Rover’s Hill Descent Control system, let’s address the more concerning issue of HDC system failure.
How to Detect HDC Failure
The most important message to be on the lookout for is “HDC Fault System Not Available.” This is displayed in the vehicle’s instrument panel when a failure in the HDC system has been detected. If you see this message, it is important that you take your Land Rover to an authorized mechanic as soon as possible.
HDC is sensitive to differences in voltage across the vehicle’s electrical systems. As such, a number of issues can lead to failure in the HDC system, including low battery life, alternator malfunction, faulty wiring, blown fuses, and software problems.
As we have said, the HDC feature works with your vehicle’s brake systems, including the Traction Control and Anti-lock Braking Systems (ABS), the latter enables the Rover to engage the brakes on each wheel independently as needed. As such, a fault in either of these systems can cause HDC to fail. If you see the “HDC Fault System Not Available” message while the brake warning light or ABS warning light are illuminated, this can indicate a failure in any or all of these systems. These failures could pose a serious danger and should be addressed by a qualified professional immediately.
European Auto Tech Can Solve Your HDC Problems
A certified Land Rover mechanic will be able to properly diagnose and fix the cause of your malfunctioning HDC. At European Auto Tech, our 
mechanics help Land Rover drivers from all over the Plano area with affordable, quality maintenance and repairs. Our five-star reviewed shop even services drivers from Allen, Dallas, Flower Mound, Frisco, Highland Park, McKinney, Park Cities, Richardson, Southlake, and University Park, TX, all of whom make the trip for the superior service we offer.
Although the Land Rover is a highly versatile off-road vehicle, it is important to regularly maintain your vehicle to avoid the accumulation of mechanical problems. We provide factory-scheduled services, diagnostic inspections, and preventative maintenance to ensure your vehicle’s optimum performance. For assistance with HDC system issues or to inquire about our services, call us at (469)-429-9992 today!
* Land Rover Defender 110 SW image credit goes to: Snap2Art_RF.