Ciera Cruiser V6-173 2.8L VIN W FI (1986)
2.
The power steering cutout switch opening during high P/S line pressure. With the A/C off, this interrupts the ground circuit for the relay coil.
The vacuum solenoid relay is energized (when the ignition is on), when the A/C is off and the power steering pressure switch is closed. (NOTE: With the
A/C off, it is assumed that the A/C high pressure cut off switch is closed.)
The resistance of the vacuum solenoid relay coil is high and the resistance of the A/C compressor clutch coil is low. Therefore, when the vacuum
solenoid relay is energized (A/C off) the voltage drop across the A/C compressor clutch coil is low and is not sufficient to engage the clutch. The A/C
clutch coil also provides a ground path for the vacuum solenoid relay coil, due to its low resistance.
CHART C-2 E-1
VACUUM THROTTLE KICKER 2.8L CARBURETED
CIRCUIT DESCRIPTION:
"Throttle Kicker" is vacuum operated and extends under the following conditions:
^
Coolant temperature below 85~C (185~F).
^
For 30 seconds after start if coolant temperature above 85~C (185~F).
^
A/C "ON" and presum cycling swich closed (clutch "ON").
^
Full turn (power steering switch open).
