Installation Instructions for T-Connector Adapter for Volvo XC70

Part Numbers:

• 118774

Tools Required:

• Trim Panel Remover
• 10mm Socket & Ratchet or Wrench
• Drill (3/32” Drill Bit)
• Wire Crimpers
• Wire Cutters
• Phillips Head Screwdriver
• Test Probe

Step-by-Step Instructions:

1. Prepare the Rear Cargo Area:

• Open the rear hatch.
• Partially remove the plastic threshold cover, side panels, and cargo trays to locate the vehicle wiring in the rear cargo area.

2. Locate the Taillight Wiring Harness:

• On both the driver and passenger sides, locate the vehicle’s taillight wiring harness.
• Disconnect the connectors carefully, ensuring not to break the locking tabs. Clean all connector surfaces to remove dirt.

3. Install the Driver-Side T-Connector:

• Insert the T-Connector end with the yellow wire between the driver’s side vehicle wiring connectors and lock it into place.
• Ensure the connectors are fully inserted with locking tabs engaged.

4. Mount the T-Connector Black Box:

• Use the provided double-sided tape to mount the black box securely on the driver’s side.
• Secure the remainder of the T-Connector harness using the provided cable ties, avoiding areas that could cut or pinch the wire.

5. Ground the White Wire:

• Locate a suitable grounding point near the connector, such as an existing ground stud, or drill a 3/32” hole.
• Secure the white wire using the provided eyelet and screw. Avoid drilling into the vehicle floor or bed.

Caution:

• Verify what is behind the surface before drilling to prevent damage or injury.

6. Route the Passenger-Side T-Connector:

• Route the T-Connector end with the green wire across the threshold to the passenger side of the vehicle.
• Insert the T-Connector between the vehicle wiring connectors on the passenger side and lock it into place.

7. Connect the Red Wire:

• On the driver’s side, route the T-Connector end with the red wire up the panel and connect it to the mating connector.
• Ensure all connections are secure with locking tabs fully engaged.

8. Connect the Power Wire:

• Locate the black 12-gauge power wire from the T-Connector black box on the driver’s side.
• Attach the provided black 12-gauge wire using the supplied yellow butt connector.
• Route the black wire along the vehicle frame or existing wiring to the battery in the engine compartment.

Warning:

• Avoid routing near hot pipes, heat shields, or the fuel tank.

9. Connect to the Vehicle Battery:

• Disconnect the negative (-) battery cable.
• Attach the yellow fuse holder to the positive (+) battery cable using the provided ring terminal.
• Connect the other end of the fuse holder to the black wire with the yellow butt connector.
• Reconnect the negative (-) battery cable and install the 15-amp fuse into the fuse holder.

10. Secure the Wiring:

- Use the provided cable ties to secure the T-Connector harness, ensuring it is not pinched, cut, or melted.

11. Reassemble the Vehicle:

- Reinstall the plastic trim panels, threshold, storage covers, floor covering, and any other items removed during installation.

12. Test the Installation:

- Test the T-Connector installation with a test light or trailer to ensure functionality.  
- Reset the vehicle’s electrical system by temporarily removing the key from the ignition.

Specifications:

• Max. stop/turn light: 1 per side (2.1 amps)
• Max. tail lights: (5.6 amps)

Safety Notes:

• Overloading circuits can cause fires. Do not exceed the towing manufacturer’s rating or the unit specifications.
• Always follow the vehicle owner’s manual and instructions provided.

Manufacturer Notes:

• Store the 4-flat connector in the rear cargo area when not in use.
• Refer to the vehicle owner’s manual for additional guidance.

Attention: This is a summary of the installation procedure. For complete installation instructions, including diagrams and detailed information from the manufacturer, please download the full installation PDF.

For technical support and assistance, our team of experts is available to help. You can reach our tech support by visiting www.trailerjacks.com or calling 877-869-6690.

Warranty Information:

• For complete warranty instructions, please download the full installation PDF.

Installation Instructions for 4-Way to 7-Way Adapter and Brake Control Wiring

Tools Required:

• Phillips Head Screwdriver
• Drill with 3/32" Drill Bit
• 10mm Socket & Ratchet or Wrench
• Wire Crimpers
• Wire Cutters
• Test Light or Multimeter
• Cable Ties

Part 1: Install the 4-Way to 7-Way Adapter

Step-by-Step Instructions:

1. Mount the Adapter:

   • Choose a suitable mounting point on the vehicle, typically near the hitch.
   • Use the provided bracket and screws to secure the adapter.

2. Connect the 4-Flat Plug:

   • Plug the 4-flat connector on the adapter into the existing 4-flat plug on the vehicle.
   • This connection enables tail lights, left turn, and right turn signals.

3. Ground the Adapter:

   • Locate a clean, solid grounding point near the adapter.
   • Drill a 3/32" hole if necessary and secure the white ground wire from the adapter using the provided screw and eyelet.

4. Leave Additional Wires Disconnected:

   • The following wires will remain disconnected until Part 2:
     • Black Wire: Power from the battery.
     • Blue Wire: Brake control output.
     • Yellow Wire: Reverse light (optional; leave disconnected unless needed).

5. Test Initial Connection:

   • Use a test light or trailer to verify functionality of the 4-way connections (tail lights, turn signals).

Part 2: Install Brake Control Wiring

Step-by-Step Instructions:

1. Mount Circuit Breakers:

   • Install two 30A circuit breakers on the firewall or another suitable location near the battery.
   • Use self-tapping screws to mount them securely.

2. Route Power Wires:

   • Connect the black 12-gauge wire from the 7-way adapter to the auxiliary side of one circuit breaker (this powers the 7-way socket).
   • Run a heavy-gauge wire from the battery's positive terminal to the battery side of this circuit breaker, using a ring terminal.
   • Run another heavy-gauge wire from the battery's positive terminal to the auxiliary side of the second circuit breaker (for the brake controller).

3. Install the Brake Controller:

   • Mount the brake controller under the dash on a firm surface.
   • Use the following connections:
     • Red Wire: Connect to the cold side of the brake switch (active only when the brake pedal is pressed).
     • Blue Wire: Connect to the blue wire on the 7-way adapter for trailer brakes.
     • White Wire: Connect to a solid ground point on the vehicle body.
     • Black Wire: Connect to the auxiliary side of the second 30A circuit breaker (provides power to the brake controller).

4. Optional: Connect Reverse Light Circuit:

   • If the trailer has a reverse light circuit, connect the yellow wire from the 7-way adapter to the vehicle’s reverse light circuit.

5. Reconnect the Battery:

   • Reattach the negative battery cable and ensure all connections are secure.
   • Insert the fuses into both circuit breakers.

6. Secure All Wires:

   • Use cable ties to secure all loose wires and prevent damage or rattling.

7. Test the System:

   • Verify functionality of all circuits (running lights, turn signals, brake lights, and brake controller output).
   • If applicable, test the reverse light circuit.

Notes:

• Most installations will only require connecting the black and blue wires from the 7-way adapter.
• Leave the yellow wire disconnected unless the trailer has a reverse light or surge brake lockout circuit.
• Always adhere to safety guidelines and verify all connections before use.

Warning: Incorrect wiring can cause damage to the vehicle or trailer. Test all connections carefully before use.

Installation Instructions for 4-Way to 7-Way Adapter and Brake Control Wiring

Tools Required:

• Phillips Head Screwdriver
• Drill with 3/32" Drill Bit
• 10mm Socket & Ratchet or Wrench
• Wire Crimpers
• Wire Cutters
• Test Light or Multimeter
• Cable Ties

Part 1: Install the 4-Way to 7-Way Adapter

Step-by-Step Instructions:

1. Mount the Adapter:

   • Choose a suitable mounting point on the vehicle, typically near the hitch.
   • Use the provided bracket and screws to secure the adapter.

2. Connect the 4-Flat Plug:

   • Plug the 4-flat connector on the adapter into the existing 4-flat plug on the vehicle.
   • This connection enables tail lights, left turn, and right turn signals.

3. Ground the Adapter:

   • Locate a clean, solid grounding point near the adapter.
   • Drill a 3/32" hole if necessary and secure the white ground wire from the adapter using the provided screw and eyelet.

4. Leave Additional Wires Disconnected:

   • The following wires will remain disconnected until Part 2:
     • Black Wire: Power from the battery.
     • Blue Wire: Brake control output.
     • Yellow Wire: Reverse light (optional; leave disconnected unless needed).

5. Test Initial Connection:

   • Use a test light or trailer to verify functionality of the 4-way connections (tail lights, turn signals).

Part 2: Install Brake Control Wiring

Step-by-Step Instructions:

1. Mount Circuit Breakers:

   • Install two 30A circuit breakers on the firewall or another suitable location near the battery.
   • Use self-tapping screws to mount them securely.

2. Route Power Wires:

   • Connect the black 12-gauge wire from the 7-way adapter to the auxiliary side of one circuit breaker (this powers the 7-way socket).
   • Run a heavy-gauge wire from the battery's positive terminal to the battery side of this circuit breaker, using a ring terminal.
   • Run another heavy-gauge wire from the battery's positive terminal to the auxiliary side of the second circuit breaker (for the brake controller).

3. Install the Brake Controller:

   • Mount the brake controller under the dash on a firm surface.
   • Use the following connections:
     • Red Wire: Connect to the cold side of the brake switch (active only when the brake pedal is pressed).
     • Blue Wire: Connect to the blue wire on the 7-way adapter for trailer brakes.
     • White Wire: Connect to a solid ground point on the vehicle body.
     • Black Wire: Connect to the auxiliary side of the second 30A circuit breaker (provides power to the brake controller).

4. Optional: Connect Reverse Light Circuit:

   • If the trailer has a reverse light circuit, connect the yellow wire from the 7-way adapter to the vehicle’s reverse light circuit.

5. Reconnect the Battery:

   • Reattach the negative battery cable and ensure all connections are secure.
   • Insert the fuses into both circuit breakers.

6. Secure All Wires:

   • Use cable ties to secure all loose wires and prevent damage or rattling.

7. Test the System:

   • Verify functionality of all circuits (running lights, turn signals, brake lights, and brake controller output).
   • If applicable, test the reverse light circuit.

Notes:

• Most installations will only require connecting the black and blue wires from the 7-way adapter.
• Leave the yellow wire disconnected unless the trailer has a reverse light or surge brake lockout circuit.
• Always adhere to safety guidelines and verify all connections before use.

Warning: Incorrect wiring can cause damage to the vehicle or trailer. Test all connections carefully before use.

Attention:

This is a summary of the installation procedure. For complete installation instructions, including diagrams and detailed information from the manufacturer, please download the full installation PDF.

Warranty Information:

For complete warranty instructions, please download the full installation PDF.

Technical Support:

For technical support and assistance, our team of experts is available to help. You can reach our tech support by visiting www.trailerjacks.com or calling 877-869-6690.