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NTC-1C: Checking Speed Control Operation

NOTE: Perform NTC-1A: CHECKING SPEED CONTROL OPERATION  before proceeding.
  1. Turn engine 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  under VERIFICATION TESTS.
  2. Inspect throttle cable. If throttle cable is damaged or misadjusted, repair as necessary. Perform TEST VER-4A: SPEED CONTROL VERIFICATION  under VERIFICATION TESTS. If throttle cable is okay, go to next step.
  3. Turn ignition off. Disconnect speed control servo connector. Disconnect Powertrain Control Module (PCM) connector. Inspect connectors. Clean or repair as necessary. Using an external ohmmeter, measure resistance of speed control vacuum solenoid control circuit between PCM connector terminal No. 56 (Tan/Red wire) and speed control servo connector terminal No. 1 (Tan/Red wire). If resistance is 5 ohms or more, repair open speed control vacuum solenoid control circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION  under VERIFICATION TESTS. If resistance is less than 5 ohms, go to next step.
  4. Measure resistance of speed control vent solenoid control circuit (Light Green/White wire) between PCM connector terminal No. 80 and speed control servo connector terminal No. 2. If resistance is less than 5 ohms, replace speed control servo. Perform TEST VER-4A: SPEED CONTROL VERIFICATION  under VERIFICATION TESTS. If resistance is 5 ohms or more, repair open speed control vent solenoid control circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION  under VERIFICATION TESTS.