2018/2019/2020 Cummins Bypass Cable Installation

1. Twist the yellow and tan wires together, ensuring a twist is made every two inches.
2. Gently detach the OBDII connector from the dash by pressing the tabs located on its sides.
3. Take out the two grey pin retainers from the back of the connector.
4. One at a time, remove the yellow and brown wires from positions 6 and 14. For 2018 models, replace the yellow wire with yellow and the brown one with tan. For 2019 and 2020 models, replace the yellow wire with tan and the brown one with yellow. NOTE: If you face issues connecting to the truck after installing the cable, try reversing the wires. Note: To remove the pins, you can use a 1.5mm wide flat terminal release tool or a sharp sewing needle.

OBDII Connector

5. Reattach the two grey pin retainers back into place.
6. Find the green “Star” connector located above the parking brake. For 2018 models, connect the harness to any available slot. For 2019 and 2020 models, insert the harness into the fifth position from the left at the bottom.

2018 Star Connector

7. Insulate and cover the pins that were removed from the OBDII connector.
8. Reinsert the OBDII connector back into its original position.

The bypass cable may also be required in the following cases:

• Modifying tire size
• Installing an aftermarket remote start system
• Utilizing a Snap-on or similar OBDII scanner
• Adding AMP Steps