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Backup Warning System Sensor Replacement

What is a Backup Warning System Sensor?

Backup warning system sensors, also known as park assist sensors, park distance control (PDC) sensors, or simply park sensors, are safety devices, proximity sensors, that detect objects behind (or in the "proximity" of) a vehicle during parking. Some vehicles come factory equipped with backup warning sensors. Aftermarket systems are also available for retrofitting a vehicle with this feature.

How does a Backup Warning System Sensor work?

When a car, truck, or SUV equipped with a backup warning system is shifted into reverse, the backup warning system scans the area behind the vehicle to locate objects that might be in the way. The backup warning sensors (park sensors) emit ultrasonic pulses that bounce off of an object and back to receptors in the sensor. When an object is detected behind the vehicle, a warning tone is heard audibly inside the passenger compartment to signal to the driver that the path is not clear. Some backup warning systems use electromagnetics instead of ultrasonic pulses. Some vehicles may also incorporate sensors that detect objects to the front or side of the vehicle.

Toyota Backup Warning System Sensor Replacement Cost Estimates

The average cost for a Backup Warning System Sensor Replacement is between $716 and $801 but can vary from car to car.

Toyota Prius AWD-e Backup Warning System Sensor Replacement Cost by Year

The average cost for a Toyota Prius AWD-e Backup Warning System Sensor Replacement is between $716 and $801 but can vary from car to car.

2022 Toyota Prius AWD-e

$784-$870

2021 Toyota Prius AWD-e

$784-$870

2020 Toyota Prius AWD-e

$716-$801

2019 Toyota Prius AWD-e

$716-$801

Disclaimer

Materials Included Under License from Toyota Motor Sales, U.S.A., Inc. License Agreement TMS1008. All information contained in any materials obtained about Toyota, Lexus, and Scion vehicles is based on the latest product information available at the time of publication, is provided “as is” without warranty of any kind, and is intended for service providers and other interested parties in Canada, Mexico, and the United States of America, including Guam, Puerto Rico, and the U.S. Virgin Islands. Specifications and procedures are subject to change without notice. This information is provided expressly for the purpose of use by professional automobile technicians who have special techniques and certifications. Repair or service by non-specialized or uncertified technicians using only this information, or without proper equipment or tools, may cause severe injury to the individual or other individuals and could possibly cause damage to the vehicle. Certain procedures or content elements may make reference to Toyota Warranty policy or practice – these policies or practices are only applicable to Toyota, Lexus, or Scion dealers.

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Backup Warning System Sensor Replacement

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What is a Backup Warning System Sensor?

How does a Backup Warning System Sensor work?

2019 Toyota Prius AWD-e Backup Warning System Sensor Replacement Cost

The average cost for a 2019 Toyota Prius AWD-e Backup Warning System Sensor Replacement is between $716 and $801.

Labor costs are estimated between $183 and $269 while parts are typically priced around $533.
This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.
For a more accurate estimate based on your location, use our Fair Price Estimator below.

What are the symptoms of a bad Backup Warning System Sensor?

A malfunctioning backup warning sensor may cause the switch that engages the backup warning system to remain lit (or display "off") even when the switch is turned on. If the vehicle is in reverse and there are objects in close proximity to the rear of the vehicle, but no warning tone is heard, one or more sensors might be bad. Some vehicles will display a dashboard warning light to alert the driver to a fault with the backup warning system.

Can I drive with a bad Backup Warning System Sensor?

Vehicles have been in operation for many years without backup warning sensors. A vehicle can certainly be driven without them. However, if a vehicle is equipped with a backup warning system and a driver assumes that the system is operational, injury or damage can occur. This safety system should be repaired as soon as possible to avoid accident or injury.

How often do Backup Warning System Sensors need replacement?

Backup warning sensors may wear out over time. The biggest problem with the sensors is probably dirt and grime that is allowed to build up. Simple cleaning of the sensors may extend their life or enable them to work properly. Of course, damage can result from a crash - even a minor one - that would render the sensors unuseable.

How are Backup Warning System Sensors diagnosed?

Diagnosing a faulty backup warning sensor is fairly simple. With the vehicle on level ground and the wheels chocked, and with the ignition in the "accessory" position, a technician will place the transmission in reverse to engage the backup warning system and then move to the rear of the vehicle near the sensors. Each of the sensors should make a faintly audible clicking sound when an object (a finger) is held a half inch or so in front of the sensor. The technician will test each sensor individually. Any sensor that does not emit a faint (but audible) clicking sound is not working. It is also necessary to make sure that the electrical connection to the sensor is operational. The technician may use a multimeter to test the connectors. A diagnostic scan to check for fault codes may be required.

How are Backup Warning System Sensors replaced?

The replacement procedure for a backup warning sensor on any vehicle will be similar: unplug the sensor, remove any retainer holding it in place, pull the sensor from its mount, install and connect the new sensor. Access to the sensor, however, may differ greatly from one vehicle to the next. On some vehicles, the sensor is easily accessed by reaching a hand inside the bumper. On others, the bumper assembly will need to be removed completely. This can be an extensive task on some vehicles. Once the new sensor(s) have been installed, the backup warning system may reset on its own, or it may need to be reset with a scan tool.

RepairPal Recommendations for Backup Warning System Sensor issues

RepairPal recommends that a driver always perform a visual check around the perimeter of a vehicle prior to driving, especially backing up. It is also recommended that backup warning sensors be kept clean, free from grime or debris, to maintain functionality.

What to look out for when dealing with Backup Warning System Sensor issues

Always check behind the vehicle before backing up. Do not rely completely on the backup warning system. It should be noted that the sensors may not be able to detect small objects below the sensors, narrow objects (like a pole), or flat objects lying on the ground. Be aware of your surroundings and allow the backup warning system to assist. Also, if a diagnostic procedure is being performed and the vehicle is to be left in reverse while the sensors are inspected, it is essential that the vehicle be situated on level ground, preferably with the wheels chocked, to prevent the vehicle from rolling and causing damage or injury.

Can I replace the Backup Warning System Sensor myself?

Anyone with intermediate DIY experience should be able to diagnose and replace the backup warning system sensors on a vehicle. It may be necessary to seek help if diagnostic trouble codes need to be read or cleared.

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