Checking the serviceability of the automatic transmission torque converter

1. Visual inspection

* Check for fluid leaks from the torque converter.
* Inspect the torque converter housing and blades for cracks, damage or wear.

2. Slip test

* Gearbox in “D” mode
* Apply the brake and press the gas pedal sharply.
*If the torque converter is faulty, significant slippage or vibration will be felt.
* A properly functioning torque converter will provide smooth acceleration.

3. Blocking test

* Gearbox in “D” or “Drive” mode
* Accelerate slowly to 40-50 km/h.
*Press the gas pedal for sudden acceleration.
* If the torque converter locks up correctly, the engine speed should decrease when shifting into higher gear.
* A faulty torque converter may not lock or may be delayed.

4. Checking the ATF fluid level

* Check the ATF fluid level with the engine warm and the transmission in Park or Neutral.
*Low fluid levels may indicate a leak that may affect torque converter performance.

5. Checking ATF pressure

* Connect the pressure gauge to the automatic transmission fluid pressure port.
* Start the engine and change all gears in ascending order.
*Compare the measured pressure with the specifications in the service manual.
* Inconsistency in pressure may indicate problems with the torque converter or other automatic transmission components.

6. Diagnostic scanner

* Connect the diagnostic scanner to the automatic transmission ECU.
*Check for torque converter related trouble codes.
* Some scanners can also display real-time fluid pressure and torque converter lockup readings.

Attention:

*Always follow the manufacturer’s instructions when performing tests.
*If you notice any signs of torque converter failure, it is recommended that you contact a qualified mechanic for further diagnosis and repair.

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