For 1990-2009 cars

## Rear Park Assist Continuously Enabled Genuine Accessory

### Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

### Circuit/System Description

The rear park assist system (RPA) is designed to assist the driver when reversing and should not be used as a substitute for safe driving practices. The RPA is equipped with a module, a warning buzzer and ultrasonic sensors. The ultrasonic sensors operate both as transmitters and receivers of ultrasonic signals. The driver is alerted to approaching objects by a sequence of pulses or continuous tones from the warning buzzer. When the driver selects reverse, power is supplied from the backup lamp relay via the RPA external relay to the RPA module activating the RPA system.

### Reference Information

#### Schematic Reference

Object Detection Schematics .

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Circuit/System Testing

1. Ignition OFF, disconnect the external relay.
2. Ignition ON, engine OFF, verify that a test lamp does not illuminate between the external relay reverse control circuit terminal 1 and ground.

⇒ | If the test lamp illuminates, test the reverse control circuit terminal 1 for a short to voltage.

3. Verify that a test lamp does not illuminate between the external relay control circuit terminal 2 and ground.

⇒ | If the test lamp illuminates, test the control circuit terminal 2 for a short to voltage.

### Repair Instructions

For component removal and installation refer to the accessory fitting instructions.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.