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Pattern Select Switch Circuit

  1. Access ECT ECU located on right side of dash, under glove box. Turn ignition on. Using a DVOM, backprobe between ECT ECU connector terminal "P" (Green/Orange wire) and ground with connector connected. See Figure.
  2. Voltage should be battery voltage with PWR (power) selected, and zero volts with NORM (normal) selected. If voltage is not as specified, go to next step. If voltage is as specified, and transmission is not functioning properly, perform symptom diagnostics. See TROUBLE SHOOTING .
  3. Access and disconnect pattern select switch connector. See Figure. Using a DVOM, check continuity between pattern select switch terminals No. 1 and 2. See Fig 1. Continuity should not be present when PWR (power) is selected, and continuity should be present when NORM (normal) is selected.
  4. If continuity is not as specified, replace pattern select switch. If continuity is as specified, check for defective wiring between the ECT ECU connector and the pattern select switch. See WIRING DIAGRAMS . Repair wiring as necessary. If wiring is okay, replace ECT ECU.
Fig 1: Identifying Pattern Select Switch Terminals
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