1. Open the hood of your Thunderbird.
2. Locate the fuse box cover, which is typically a black or gray plastic cover with various markings indicating its contents.
3. Remove the fuse box cover by gently prying it open, usually with the help of your fingers or a flat-head screwdriver.
4. Inside the fuse box, you should find a diagram or label indicating the location and function of each fuse and relay.
5. Locate the relay labeled "PCM power relay" or something similar. It may also be labeled as "Engine control module relay."
6. The PCM power relay is typically a small, square-shaped component with multiple terminals or pins.
7. Take note of the position or slot number of the PCM power relay, as you may need to refer to it if you need to replace the relay in the future.
If you still have trouble locating the PCM power relay, refer to your Thunderbird's owner's manual or seek help from a qualified automotive mechanic or electrician.