Why does my Toyota say radar cruise control is unavailable?

If your Toyota vehicle's radar cruise control system is displaying an "unavailable" message, there could be a few potential reasons for this. Radar cruise control is an advanced driver assistance feature that uses sensors to automatically maintain a safe following distance behind the vehicle in front of you. However, there are certain conditions that can cause this system to become temporarily unavailable.

Potential Reasons for Radar Cruise Control Unavailability

• Sensor Obstruction: The radar sensors located on the front of your Toyota may be obstructed by dirt, snow, ice, or other debris, preventing them from functioning properly. Ensure the sensors are clean and unobstructed.


• Environmental Conditions: Extreme weather conditions like heavy rain, fog, or snow can interfere with the radar sensors, causing the system to become unavailable. The sensors rely on clear visibility to operate effectively.


• Vehicle Speed: Radar cruise control may be unavailable at very low speeds, typically below 20-25 mph, or when the vehicle is stopped. This is a normal limitation of the system.


• System Malfunction: In some cases, a technical issue with the radar cruise control system itself may cause it to become unavailable. This could be due to a sensor failure, wiring problem, or other internal component failure.

If the radar cruise control system remains unavailable despite addressing these potential issues, it's recommended to consult your Toyota dealer or a qualified automotive technician to diagnose and resolve the problem.

Troubleshooting Steps

• Check the front of your Toyota for any obstructions or debris on the radar sensors.


• Ensure the sensors are clean and unobstructed.


• Monitor the weather conditions and try using the radar cruise control system again when the weather improves.


• Check your vehicle's speed and ensure it's within the operating range of the radar cruise control system.


• If the issue persists, contact your Toyota dealer or a qualified technician for further diagnosis and repair.

By understanding the potential reasons for radar cruise control unavailability, you can take the necessary steps to troubleshoot and resolve the issue, ensuring your Toyota's advanced driver assistance features are functioning as intended.

Why is my radar cruise control unavailable?

Radar cruise control is unavailable primarily because the front radar sensor or camera is blocked or dirty. Other causes include a low speed (under 252525-353535 mph), a misaligned sensor from a minor front-end impact, or an issue with the system's fuse or electrical components. To troubleshoot, first, thoroughly clean the front sensors and windshield. If that doesn't work, restart the vehicle or check for other issues like a blown fuse or low speed. 
Common solutions

• Clean the sensors: Wipe the front radar sensor (usually behind the front grille or bumper) and the inside of the windshield (where the camera is located) with a soft cloth. Dirt, snow, ice, bugs, or heavy rain can all block the sensors. 
• Restart the vehicle: Turn the car off and on again. This can often clear temporary glitches in the system. 

This video demonstrates how to clean the radar sensor and restart the vehicle to fix the issue: 1mDashboard warning lights YouTube · Jul 3, 2025
Other potential causes

• Low speed: Some systems require you to be going over a certain speed (e.g., 252525-353535 mph) before radar cruise control can be engaged. 
• Sensor misalignment: A minor bump to the front of the car can slightly misalign the sensor, causing it to become temporarily unavailable. If cleaning doesn't work, professional recalibration may be needed. 
• Blown fuse: A blown fuse for the cruise control system will prevent it from working. You can check your owner's manual to find the location of the fuse and replace it if it's the problem. 
• Other system issues: Less common issues can include a vacuum leak, a faulty speed sensor, or a bad engine control module. If the problem persists after trying the simple fixes, it may be best to have the vehicle inspected by a mechanic. 

You can watch this video to learn how to check the radar sensor and address other potential causes of the issue: 1mMaciej PiotrowskiYouTube · Jun 12, 2019

Why is my cruise control not available?

Cruise control may not be available due to a blown fuse, faulty brake light switch, or a problem with the cruise control switch itself. For vehicles with adaptive cruise control, a dirty or blocked camera or radar sensor is a common cause, often caused by dirt, snow, ice, or condensation on the windshield. Other issues could include a faulty vehicle speed sensor, electrical problems, or a "Check Engine" light being on.
 
Common causes and solutions
This video demonstrates how to inspect and replace a faulty brake light switch: 1mThe DieseldogYouTube · May 23, 2024

• Check for simple, external issues: 
  • For adaptive cruise control: Clean the front radar and camera sensors. These are often located behind the front bumper or on the windshield. Wipe them with a microfiber cloth and gentle cleaner, as dirt, bugs, snow, or heavy wax can block them. 
  • For any cruise control: Check your brake lights. If one is out, cruise control may not work because the system disengages when a brake light switch is faulty. 
• Inspect electrical components: 
  • Blown fuse: A blown fuse can disable the entire system. Check your car's fuse box and replace the cruise control fuse if it's blown. 
  • Faulty switch: The cruise control switch itself can fail. A malfunctioning brake pedal switch is another common issue, as it's used to disengage the system. 
• Consider vehicle performance issues:
  • Check Engine Light: If your "Check Engine" light is on, it could be the reason for the cruise control malfunction, as many modern systems will disable cruise control when there's an engine-related problem. 
  • Vehicle speed sensor: A bad speed sensor can prevent the system from working because it can't accurately read the car's speed. 
• For modern and older systems:
  • For older cars: Vacuum leaks or a broken vacuum actuator can cause issues. 
  • For newer cars: Problems with wiring, connectors, or the main control module could be the cause. 

When to see a mechanic
If the simple checks don't solve the problem, it's best to take your vehicle to a qualified mechanic for a professional diagnosis, especially if you have an older or more complex system or if the "Check Engine" light is on. 
This video explains common symptoms of a malfunctioning cruise control system: 47sCar Care HacksYouTube · Sep 21, 2023

How to clean a radar sensor?

To clean a car's radar sensor, use a soft cloth, like a microfiber cloth, to gently wipe away dirt, snow, ice, or grime. For stubborn spots, you can dampen the cloth with water or a mild car washing detergent. Avoid abrasive materials, strong impacts, or stickers on the sensor's surface to prevent damage. 
This video demonstrates how to clean a radar sensor: 50sVehicle FreakYouTube · Sep 29, 2023
Step-by-step cleaning guide

1. Locate the sensor: The sensor is typically behind the front grille, often integrated into the front emblem or bumper. Check your owner's manual for the exact location. 
2. Wipe with a soft cloth: Use a dry, soft cloth (like microfiber) to gently wipe the sensor's surface. 
3. Use a damp cloth for stubborn dirt: If dirt, bugs, or grime remain, lightly dampen the cloth with water or a mild car washing detergent and wipe again. 
4. Dry the sensor: Use a separate dry, soft cloth to gently dry the sensor completely. 
5. Inspect for damage: After cleaning, check for any physical damage to the sensor or its cover. 

Important considerations

• Avoid abrasive materials: Never use abrasive cloths or materials that could scratch the sensor's surface. 
• Do not use excessive force: Avoid applying strong impact or using excessive force when cleaning. 
• Avoid stickers: Do not place any stickers, including transparent ones, on the radar sensor or its cover. 
• Check your owner's manual: Refer to your vehicle's owner's manual for specific cleaning instructions and sensor locations for your model. 

Where is the radar cruise control sensor?

The radar cruise control sensor is typically located behind the front grille or bumper, often concealed by a plastic cover, a filler panel, or even the vehicle's emblem. A forward-facing camera, which works with the radar, is usually located behind the windshield, in front of the rearview mirror.
 
This video shows the location of the radar sensor and how to clean it on a Toyota: 1mCOLD STREAMYouTube · Dec 3, 2023

• Location: Look at the front of your car, typically in the lower grille area or center of the front bumper. Some manufacturers hide the sensor behind the manufacturer's emblem on the grille. 
• Function: The sensor, along with a front-facing camera, helps the system detect vehicles ahead to maintain a safe following distance. 
• Maintenance: Keep the sensor area clean, as dirt, snow, ice, or even a bumper sticker can obstruct it and cause the system to malfunction. 
• Caution: Avoid placing stickers or anything else on the sensor's cover, as this can interfere with its function. If the front of the vehicle has been damaged, the sensor's alignment may be affected, and it should be professionally inspected and calibrated.