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Test SC-1C: Checking Speed Control Operation

NOTE: Perform TEST CS-1A: CHECKING SPEED CONTROL OPERATION  before proceeding.
  1. Turn ignition off. Observe vacuum gauge for 10 seconds. If vacuum holds for at least 10 seconds, go to next step. If vacuum does not hold for at least 10 seconds, replace vacuum check valve. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  2. Inspect throttle cable. If throttle cable is disconnected or damaged, repair as necessary. Perform TEST VER-4A: SPEED CONTROL VERIFICATION . If throttle cable is not disconnected or damaged, go to next step.
  3. Turn ignition off. Disconnect speed control servo connector. Disconnect Powertrain Control Module (PCM) connector. Using a DVOM, check resistance of speed control vacuum solenoid control circuit between speed control servo connector and PCM connector terminal No. 56. See SPEED CONTROL SERVO CONNECTOR WIRE IDENTIFICATION  table and PCM CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open speed control vacuum solenoid control circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  4. Using a DVOM, check resistance of speed control vent solenoid control circuit between speed control servo connector and PCM connector terminal No. 80. See SPEED CONTROL SERVO CONNECTOR WIRE IDENTIFICATION  table and PCM CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, replace speed control servo. See TEST VER-4A: SPEED CONTROL VERIFICATION . If resistance is 5 ohms or more, repair open speed control vent solenoid control circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
SPEED CONTROL SERVO CONNECTOR WIRE IDENTIFICATION

Application Wire Color
Brake Switch Output Circuit Dark Blue/Red
Speed Control Vacuum Solenoid Control Circuit Tan/Red
Speed Control Vent Solenoid Control Circuit Light Green/Red
Ground Black
PCM CONNECTOR WIRE IDENTIFICATION

Application Wire Color
PCM Terminal No. 56
Speed Control Vacuum Solenoid Control Circuit Tan/Red
PCM Terminal No. 80
Speed Control Vent Solenoid Control Circuit Light Green/White