Diagnostic Routine AK

Diagnostic Routine AK

Diagnostic Overview

The Trailer Reversing Lamps Are Inoperative

Refer to Wiring Diagram Set 11 for schematic and connector information Electrical Diagrams.

Refer to Wiring Diagram Set 95 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Trailer Reversing Lamps .

Visual Inspection and Diagnostic Pre-checks

- Inspect the BJB (Battery Junction Box) fuse 60 (10A).

- Inspect the vehicle reversing lamps for correct operation.

- Inspect the trailer tow connector for damage.

Pinpoint Test

NOTE: Before beginning diagnostics, visually inspect the trailer tow connector mounted on the bumper for signs of corrosion or damage. Repair or install a new trailer tow connector as required.

1. CHECK FOR VOLTAGE THROUGH THE TRAILER TOW CONNECTOR

1. Apply the parking brake.

2. Ignition ON.

3. Select REVERSE.

4. Measure:





Is the voltage greater than 11 volts?








2. CHECK FOR VOLTAGE TO THE TRAILER TOW CONNECTOR (VEHICLE HARNESS)

1. Ignition OFF.

2. Disconnect: Trailer Tow Connector.

3. Ignition ON.

4. Select REVERSE.

5. Measure:





Is the voltage greater than 11 volts?








3. CHECK THE TRAILER TOW REVERSING LAMP RELAY

1. Ignition OFF.

2. Disconnect: Trailer Tow Parking Lamp Relay.

3. Substitute a known good relay.

4. Ignition ON.

5. Select REVERSE.

6. Measure:





Is the voltage greater than 11 volts?








4. CHECK THE TRAILER TOW REVERSING LAMP RELAY COIL VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

1. Select REVERSE.

2. Measure:





Is the voltage greater than 11 volts?








5. CHECK THE TRAILER TOW REVERSING LAMP RELAY BJB (Battery Junction Box) VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

1. Select PARK.

2. Ignition OFF.

3. Measure:





Is the voltage greater than 11 volts?








6. CHECK THE TRAILER TOW REVERSING LAMP RELAY GROUND CIRCUIT FOR AN OPEN

1. Measure:





Is the voltage greater than 11 volts?