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Inoperative Cruise Control

NOTE: Make all tests with transmission shift lever in "PARK" position and parking brake "ON".
  1. Check "Gauges" fuse. If fuse is blown, check speed control wiring for short circuit. If fuse is not the problem and Erratic Cruise Performance Trouble Shooting  checks out O.K., turn ignition to "RUN" position. Slide "CRUISE" switch to "ON" position.
  2. Disconnect the 2 wire connector from transducer. Connect 12 volt test light to "Engage" terminal in connector and ground.
  3. Repeat step  2) using "Hold" connector terminal.
  4. If test light is off in step  2) or 3)  , check for open circuit in wire. See Figure and perform "SET-COAST" Switch Test.
  5. If test light is "on" in step  2) and 3)  , check if transducer is well grounded. If transducer is grounded, remove it for repair.
  6. If test light is "off" in step  2) and 3)  , check for open circuit in wire (brown) between engagement switch connector and brake switch. Check brake switch for voltage at both terminals with ignition in "RUN" position and "CRUISE" switch in "ON" position. Check for open circuit in wire from brake release switch to "CRUISE" switch to fuse panel plug-in. Check engagement switch operation and replace if necessary.