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For 1990-2009 cars only

Object Detection Description and Operation UFR

Table 1: Rear Object Detection System Tone Activation
Table 2: Front Object Detection System Tone Activation

The dual object detection system is designed to identify and notify the driver of an object in front and at the rear of the vehicle. The dual object detection system consists of an object alarm module, eight object alarm sensors, an object alarm speaker, and a switch. The distance and location of the object is determined by the eight object alarm sensors. Four object alarm sensors are located in the rear bumper and four are located in the front bumper.

Object Alarm Module

The object alarm module provides an 8 V reference and a low reference to each of the object alarm sensors. The object alarm module contains the logic needed to receive the individual signals from each of the sensors and determine the location and distance of an object. As the vehicle gets closer to an object the object alarm speaker will sound.

Object Alarm Sensors

The ultrasonic sensors are located in the front and rear bumpers of the vehicle. The sensors are used to determine the distance between an object and the bumper. When the transmission is in reverse the front and rear sensors are activated. If the front and rear sensors simultaneously detect an object at equal distances the rear sensors will be given priority. When the objects are not at equal distances the object closest to the vehicle will be given priority. Each sensor emits an ultrasonic frequency which is reflected off an object located behind or in front of the vehicle. The reflections are received by the sensors. The time difference between when the frequency was emitted and when the reflection is received is used to determine the distance to the object. This information is sent to the object alarm module.

Object Alarm Speaker

The object alarm speaker will sound when the ultrasonic sensors detect an object in the vehicles path. The following tables shows the object distance from the vehicle and the tone duration of the object alarm speaker.

Rear Object Detection System Tone Activation

Object Distance (MM)

Tone Duration ON (MS)

Tone Duration OFF (MS)

Less than 300

Continuous

 

300-600

75

75

600-900

75

150

900-1200

75

225

1200-1500

75

300

1500-1800

75

375

1800-2100

75

450

2100-2500

75

525


Front Object Detection System Tone Activation

Object Distance MM

Tone Duration ON (MS)

Tone Duration OFF (MS)

Less than 300

Continuous

0

300-600

75

75

600-900

75

225

900-1200

75

450

Object Detection Switch

The object detection switch is equipped with a light that will illuminate when the system is activated. The switch allows the driver to enable or disable the object detection system. The switch light will flash rapidly when it is pressed if there is a malfunction present with the object detection system.

Object Detection Operation

The object detection system is automatically activated when the vehicle ignition is on, the park brake is released and the transmission is in reverse or drive. When the transmission is in drive the front sensors will activate and the object alarm speaker will sound. If the transmission is in reverse the front and rear sensors will activate and the object alarm speaker will sound. If the object alarm speaker does not sound there is a malfunction with the object detection system. The object detection system will automatically deactive when the vehicle speed exceeds 25 km/h (15 mph).

Object Detection Description and Operation UD7

The rear object detection system consists of four object alarm sensors located in the rear bumper, a object alarm module, an object alarm speaker, and a switch. The object detection system is designed to identify and notify the driver of an object in the path of the vehicle. The distance and location of the object is determined by the alarm sensors.

Object Alarm Module

The object alarm module provides an 8 V reference and a low reference to each of the object alarm sensors. The object alarm module contains the logic needed to receive the individual signals from each of the sensors and determine the location and distance of an object. As the vehicle gets closer to an object the object alarm speaker will sound.

Object Alarm Sensors

The ultrasonic sensors are located in the rear bumper of the vehicle. The sensors are used to determine the distance between an object and the bumper. When the transmission is in reverse the rear sensors are activated. Each sensor emits an ultrasonic frequency which is reflected off an object located behind the vehicle, the reflections are received by the sensors. The time difference between when the frequency was emitted and when the reflection is received is used to determine the distance to the object. This information is sent to the object alarm module.

Object Alarm Speaker

The object alarm speaker will sound when the ultrasonic sensors detect an object in the vehicles path. The following table shows the object distance from the vehicle and the tone duration of the object alarm speaker.

Rear Object Detection System Tone Activation

Object Distance (MM)

Tone Duration ON (MS)

Tone Duration OFF (MS)

Less than 300

Continuous

 

300-600

75

75

600-900

75

150

900-1200

75

225

1200-1500

75

300

1500-1800

75

375

1800-2100

75

450

2100-2500

75

525

Object Detection Switch

The object detection switch is equipped with a light that will illuminate when the system is activated. The switch allows the driver to manually enable or disable the object detection system. The switch light will flash rapidly when it is pressed if there is a malfunction present with the object detection system.

Object Detection Operation

The rear object detection system is automatically activated when the vehicle ignition is on, the park brake is released and the transmission is in reverse. When the transmission is in reverse the rear sensors will activate and the object alarm speaker will sound. If the object alarm speaker does not sound there is a malfunction with the object detection system. The object detection system will automatically deactive when the vehicle speed exceeds 25 km/h (15 mph).

Objects attached to the vehicle

If an object is attached to the vehicle, the object detection system will automatically deactivate approximately 10 seconds after the vehicle speed exceeds 15 km/h (9 mph). The object detection will be reactivated automatically when the object is removed or the ignition is switched OFF and then ON again.