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No Lock-Up

  1. Warm engine to normal operating temperature. Locate check connector near left strut tower in engine compartment. See Figure . Install Digital Volt-Ohmmeter (DVOM) between cavity No. 17 of check connector and body ground. See Figure .
  2. Road test vehicle and ensure voltage at cavity No. 17 is 3-7 volts in lock-up range. If voltage is correct, lock-up solenoid, torque converter or transmission is defective.
  3. If voltage is not as specified, obtain access to ATCM, located near center console. See Figure . Note ATCM electrical connector terminal identification. See Figure . Using DVOM, backprobe cavities No. 19 and 22 of ATCM electrical connector with connector installed on ATCM. See Figure .
  4. No voltage should exist with brake pedal released. Approximately 10-14 volts should exist with brake pedal depressed. If voltage is not as specified, check for defective brakelight switch or wiring circuit.
  5. If voltage is as specified, check for defective ATCM power source or ground connections. Check for defective throttle position sensor or wiring.
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