Temperature Cut-Off Relay
WARNING: This page does not describe the selected car, but rather 38 other vehicles, including the 1987 Pontiac Sunbird, 1987 Pontiac Safari, 1987 Pontiac Grand Prix, 1987 Pontiac Grand Am, and 1987 Pontiac Firebird. However, it is still accessible from the selected car via links, so may be relevant.
The temperature cut-off relay is operated by a temperature switch in the coolant system. If engine temperature rises to an excessive level, the switch opens. This cuts power to the relay, interrupting compressor operation.