BMW 435i Backup Warning System Sensor Replacement Cost

Know what price you should pay to get your vehicle fixed.

The average cost for a BMW 435i backup warning system sensor replacement is between $1,219 and $1,254. Labor costs are estimated between $132 and $167 while parts are priced at $1087. Estimate does not include taxes and fees.
Note about price: The cost of this service or repair can vary by location, your vehicle's make and model, and even your engine type. Related repairs may also be needed. Talk with a RepairPal Certified shop to learn which repairs might be right for you.

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.

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 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.