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Circuit/System Testing

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  1. Ignition OFF, disconnect the harness connector at the B14A automatic transmission output shaft speed sensor. Inspect the automatic transmission output shaft speed sensor, harness, and connector pins for metallic debris and the hybrid direct, 2-3-4 clutch housing assembly machined teeth for damage or misalignment. Even one bent or misaligned tooth, and or contact with the automatic transmission output shaft speed sensor, may cause this DTC to set. Proper torque of 9-13 (80-115 lb in) to the automatic transmission output shaft speed sensor mounting bolt is critical to proper output speed sensor operation. The hybrid system is very sensitive to the OSS signal for overall operation.
    • If damage is observed, replace the damaged component.
  2. Ignition ON, test for 8.3-9.3 V between the OSS supply voltage circuit terminal A and ground.
    • If less than the specified range, test the OSS supply voltage circuit for an open/high resistance or a short to ground. If the circuit tests normal, replace the Q8 control solenoid valve assembly.
    • If greater than the specified range, test the OSS supply voltage circuit for a short to voltage. If the circuit tests normal, replace the Q8 control solenoid valve assembly.
  3. Ignition Off, connect the red lead of J 38522  variable signal generator to the OSS signal circuit terminal B and the black lead to the OSS supply voltage circuit terminal A.
  4. Adjust the J 38522  variable signal generator Signal to 8V, the Frequency to 120 and the Percent Duty Cycle to 50.
  5. Ignition ON, verify the Transmission OSS parameter is between 100-400 RPM.
    • If the Transmission OSS parameter is not within the specified range, test the Transmission OSS signal circuit for an open/high resistance, short to ground, or a short to voltage. If the circuit tests normal, replace the Q8 control solenoid valve assembly.
    • If the Transmission OSS parameter is within the specified range, replace the B14A automatic transmission output shaft speed sensor.
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