Speed Control Slows Down By Itself

Fig. 9 PCM 40-Way Connectors:

Test vehicle speed sensor. If sensor fails replace sensor, if it passes perform the following test:
1. Perform the speed control switch test on the SET/COAST switch, if it fails replace switch.
2. If the switch passes, conduct the vacuum supply test.
3. If it passes, conduct the servo vacuum test, if it fails replace servo.
4. If it passes, test continuity of pin 2 of harness connector to PCM pin 80 for intermittent open. Wiggle wires while performing this test. If continuity to pin 80, repair harness for open.
5. If no continuity, replace the PCM.