Special Testing Procedures
Special Testing Procedures
The special tests are designed to aid the technician in diagnosing the hydraulic and mechanical portions of the transaxle.
Engine Idle Speed Check
Refer to Computers and Control Systems Information for diagnosis and testing of the engine idle speed.
Line Pressure Test
NOTICE: Carry out the Line Pressure Test prior to carrying out the Stall Speed Test. If the line pressure is low at stall, do not carry out the Stall Speed Test or further transaxle damage will occur. Do not maintain Wide Open Throttle (WOT) in any range for more than 5 seconds.
This test verifies that the line pressure is within specification.
1. Connect the Transmission Fluid Pressure Gauge to the line pressure tap.
2. Start the engine and check the line pressures. Refer to the Line Pressure Chart to determine if the line pressure is within specification.
Line Pressure Chart
a All pressures are approximate.
3. If the line pressure is not within specification, see the Line Pressure Diagnosis Chart for line pressure concern causes.
4. When the pressure tests are complete, install the line pressure tap plug.
- Tighten to 12 Nm (106 lb-in).
Line Pressure Diagnosis Chart
Stall Speed Test
WARNING: Block all wheels, set the parking brake and firmly apply the service brake to reduce the risk of vehicle movement during this procedure. Failure to follow these instructions may result in serious personal injury.
NOTICE: Carry out the Line Pressure Test prior to carrying out the Stall Speed Test. If the line pressure is low at stall, do not carry out the Stall Speed Test or further transaxle damage will occur.
The Stall Speed Test checks:
- torque converter operation and installation.
- holding ability of the forward clutch.
- reverse clutch.
- planetary One-Way Clutch (OWC).
- engine driveability concerns.
Conduct this test with the engine coolant and transmission fluid at correct levels and at normal operating temperature.
Apply the park brake firmly for each Stall Speed Test.
Stall Speed Chart
1. Connect the scan tool.
2. NOTE: If the recorded rpm exceeds the maximum limits, release the accelerator pedal immediately, clutch slippage is indicated.
In each of the following ranges D, L and R, press the accelerator pedal to Wide Open Throttle (WOT). Do not hold the throttle open for more than 5 seconds at a time.
3. Note the results in each range.
4. After each range, move the selector lever to NEUTRAL and run the engine at 1,000 rpm for about 15 seconds to cool the torque converter before going to the next test.
5. Use the stall speed diagnosis chart for corrective actions.
6. If stall speeds were too high, see the Stall Speed Diagnosis Chart. If stall speeds were too low, first check engine idle speed and tune up. If engine is OK, remove torque converter and check TCC (Torque Converter Clutch) for slippage.
Stall Speed Diagnosis Chart