First, remove the wiring harness connector from the brake fluid reservoir level switch on the side of the reservoir (to service the brake fluid level sensor/switch). Next, you press in on the opposite end of the brake fluid level switch, it's on the right hand side of the reservoir and it's securing to the reservoir with retaining tabs. While the retaining tabs are compressed, take grasp of the connector end of the brake fluid level switch and pull it out of the master cylinder brake fluid reservoir. To install, push the brake fluid level switch into the left side of the brake fluid reservoir until the retaining tabs will lock it in place. As the final step, connect the vehicle wiring harness connector to the brake fluid level switch.