Backup Warning System Sensor Replacement Cost Estimate

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.

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 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.