For 1990-2009 cars

## Trailer Connector Switch Malfunction Holden Genuine Accessory

### Diagnostic Instructions

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

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category Circuit/System Description.

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Object Detection System - Automatic Disable Ground Provision | 2 | 1 | 1 | --
1. Object Detection System Inoperative. 2. Object Detection System Automatic Disable Mode Inoperative.

### Circuit/System Description

The trailer patch harness connectors are connected between the designated inline connectors of the exterior lighting system. This connection allows integration of the lighting system of the trailer to the exterior lighting of the vehicle. The wiring harness of the trailer lamps is connected to the vehicle through the trailer connector. Refer to Trailer Connector/Provision Component Views

If the vehicle is fitted with a genuine Holden object detection system, the ground circuit of this system is connected to a Reed switch in the trailer connector. Opening the trailer connector cover actuates the switch to open circuit condition and disables the rear object detection system.

### Diagnostic Aids

The following is a brief description of potential causes which may aid in diagnosis:

Missing or broken trailer connector cover will actuate the trailer connector switch to the open position and will disable the Object Detection System.

### Reference Information

#### Schematic Reference

Trailer Connector/Provision Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Object Detection Description and Operation

#### Component View Reference

Trailer Connector/Provision Component 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 trailer connector.
2. Test for less than 1.0 ohm between the ground circuit terminal 3 and ground.

⇒ | If greater than the specified value, test the ground circuit for an open/high resistance.

3. Ignition OFF, disconnect the inline connector X436.
4. Trailer connector cover CLOSED, test for less than 1.0 ohm between the ground circuit terminal 1 and ground.

⇒ | If greater than the specified value, test the ground circuit for an open/high resistance. If the circuit tests normal, test the trailer connector switch.

5. Trailer connector cover OPEN, test for infinite resistance between the ground circuit terminal 1 and ground.

⇒ | If not the specified value, test the ground circuit for short to ground. If the circuit tests normal, test the trailer connector switch.

### Component Testing

#### Trailer Connector Switch Test

1. Ignition OFF, remove the upper half cover of the trailer connector.
2. Trailer connector cover CLOSED, test for less than 1.0 ohm between ground circuit terminal 8 and signal circuit terminal 9.

⇒ | If greater than the specified value, replace the trailer connector assembly.

3. Trailer connector cover OPEN, test for infinite resistance between ground circuit terminal 8 and signal circuit terminal 9.

⇒ | If not the specified value, replace the trailer connector assembly.

### Repair Instructions

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

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.