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Test SC-1B: Checking Speed Control Operation

NOTE: Perform TEST SC-1A: CHECKING SPEED CONTROL OPERATION  before proceeding.
  1. While observing scan tool display, move gear selector to drive. If scan tool displayed switch status D/R, go to next step. If scan tool did not display switch status D/R, perform DTC P1899-A: PARK/NEUTRAL SWITCH STUCK IN PARK OR IN GEAR .
  2. Turn ignition off. Disconnect speed control servo connector. Inspect connector for damaged or pushed out terminals. If connector is okay, go to next step. If connector is not okay, repair as necessary. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  3. Using a DVOM, check resistance of ground circuit between speed control servo connector and ground. See SPEED CONTROL SERVO CONNECTOR WIRE IDENTIFICATION  table. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-4A: SPEED CONTROL VERIFICATION .
  4. Reconnect speed control servo connector. Turn ignition on. Using scan tool, actuate speed control vent solenoid. Using a 12-volt test light, backprobe between speed control brake switch output switch output circuit and ground. See SPEED CONTROL SERVO CONNECTOR WIRE IDENTIFICATION  table. If test light is brightly illuminated, go to next step. If test light is not brightly illuminated, perform TEST SC-4A: CHECKING BRAKE SWITCH SENSE .
  5. Start engine. Allow engine to idle for one minute. Turn engine off. Turn ignition on. Using scan tool, actuate speed control servo solenoids. Observe throttle assembly. If throttle opens and closes, perform TEST SC-5A: CHECKING BRAKE SWITCH SENSE . If throttle does not open and close, go to next step.
  6. Turn ignition off. Disconnect vacuum supply to speed control servo. Connect a vacuum gauge to disconnected hose. Start engine. Observe vacuum gauge. If vacuum gauge reads manifold vacuum, perform TEST SC-1C: CHECKING SPEED CONTROL OPERATION . If vacuum gauge does not read manifold vacuum, repair leak or restriction in vacuum supply. 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
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