Chart No. 5, Vehicle Speed Sensor Circuit Test

With the main switch in the On position, turn the Set switch to the On position to set desired speed. The control unit sends current to the electromagnetic clutch coil of the actuator. This attracts the clutch plate and also illuminates the Cruise indicator light. When the ring gear of the planetary pinion is secured, the control unit causes the DC motor to be switched On.
Rotation of the DC motor is transmitted to the worm gear, then the worm wheel, sun gear, then the planetary pinion. Because the ring gear is secured at this time, the planetary pinion rotates while revolving around the sun gear. Because the planetary pinion is installed into the carrier, the carrier and the selector driveshaft unified with it, as well as the selector, are caused to rotate.
The change in direction of rotation of the selector is accomplished by reversing the direction of current flow to the motor which is regulated by the control unit.
The current flow to the electromagnetic clutch is interrupted if the main switch is turned off, or if operation of the cruise control system is cancelled as a result of the input of a cancel signal to the control unit. This may be done by activation of the stop light switch, clutch switch, or the inhibitor switch.
As a result of this interruption, the clutch plate returns from the electromagnetic clutch side to the ring gear side by the force of the spring. The ring gear then becomes free.
When the ring gear becomes free, the planetary pinion releases from the sun gear, releasing the selector to its original position.
Measure voltage at terminal 8, testing the electromagnetic clutch coil transistor. Ensure the cruise control main switch is in the On position. Voltage should measure 0 volts.
Measure voltage at terminal 9, testing the DC motor drive (Pull side). Test during acceleration by use of the Resume switch. Voltage should measure 0 volts.
Measure voltage at terminal 9, testing the DC motor drive (Rel side). Test during speed reduction by use of the Set switch. Voltage should measure 12 volts.
Measure voltage at terminal 20, testing the DC motor drive (Pull side). Test during acceleration by use of the Resume switch. Voltage should measure 12 volts.
Measure voltage at terminal 20, testing the DC motor drive (Rel side). Test during speed reduction by use of the Set switch. Voltage should measure 0 volts.