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Shift Points Too High Or Low

  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 cavities No. 3 and 17 of check connector. See Figure .
  2. Turn ignition on. Note if voltage changes with throttle opening. If voltage changes with throttle opening, proceed to step 6). If voltage does not change with throttle opening, proceed to step 3).
  3. 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.
  6. Obtain access to ATCM, located near center console. See Figure . Note ATCM electrical connector terminal identification. See Figure . Using DVOM, backprobe cavities No. 8 and 19 of ATCM electrical connector with connector installed on ATCM. See Figure .
  7. Check voltage with pattern select switch in POWER (depressed) and NORMAL (released) operating positions. Voltage should be 10-14 volts with switch in POWER position and one volt with switch in NORMAL position. If voltage is as specified, ATCM or transmission is defective. If voltage is not as specified, check for defective pattern select switch or wiring circuit.
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