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Hydraulic Pressure Testing




Pressure testing can reveal the cause (not the symptom) of most transaxle problems. Hydraulic pressure testing verifies the proper functioning, or malfunctioning, of the following hydraulic components:
- Oil pump
- Regulator valve
- Hydraulic circuits

Transaxle problems can be isolated to an electronic or hydraulic/mechanical component. The hydraulic pressure test is a helpful tool in determining whether the problem is electronic or hydraulic/mechanical.

Though reference must be made to other areas for testing purposes, sequence, pressure tap readings and test results, there are some general guidelines that apply to this procedure, as follows:
- Verify proper fluid level and condition.
- Verify and correct for proper gearshift linkage adjustment.
- Verify that electrical connectors associated with the transaxle are properly connected and are clean and secure.
- Allow the transaxle to reach operating temperature before testing.

Any of the above conditions, if not checked and/or corrected, can result in false readings and inaccuracies.