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Circuit/System Testing

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  1. Ignition ON, test for 8.3-9.3 V between the automatic transmission output shaft speed sensor ignition circuit terminal A and ground.
    • If less than the specified range, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the Q8 control solenoid valve assembly.
    • If greater than the specified range, test the ignition circuit for a short to voltage. If the circuit tests normal, replace the Q8 control solenoid valve assembly.
  2. Ignition Off, connect the red lead of J 38522  generator to the signal circuit terminal B and the black lead to the ignition circuit terminal A.
  3. Adjust the J 38522  generator to 8 V, the Frequency to 120 Hz and the Percent Duty Cycle to 50 percent.
  4. Ignition ON, verify the scan tool Transmission OSS parameter is between 100-400 RPM.
    • If not within the specified range, test the signal circuit for a short to voltage short to ground open/high resistance. If the circuit tests normal, replace Q8 control solenoid valve assembly.
  5. If all circuits test normal, test or replace the B14A Automatic Transmission Output Shaft Speed Sensor.
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