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Line Pressure Test




5R44E and 5R55E

Line Pressure Test

NOTICE: Carry out Line Pressure Test prior to carrying out Stall Speed Test. If line pressure is low at stall, do not carry out Stall Speed Test or further transmission damage will occur. Do not maintain Wide Open Throttle (WOT) in any gear range for more than 5 seconds. Stall Speed Test

NOTE: Certain sensor failures may cause high Electronic Pressure Control (EPC), failure mode effect management actions. Be sure that self-test and electrical repairs have been carried out, or test results may be incorrect.

This test verifies that the line pressure is within specifications.










1. Connect Transmission Fluid Pressure Gauge to the line pressure tap on the transmission and monitor engine rpm with a scan tool.

2. Start the engine, increase and maintain 1,000 engine rpm and check line pressures. Refer to the line pressure chart to determine if line pressure is within specifications.

Line Pressure Chart:





3. If line pressure is not within specifications, check EPC pressure.










4. Connect a Transmission Fluid Pressure Gauge to EPC pressure tap.

5. Start the engine, increase and maintain 1,000 engine rpm and check EPC pressure. See the line pressure chart for specification.

6. If EPC pressure is not within specification, Go To Pinpoint Test D Testing and Inspection to diagnose EPC operation. If EPC operation is OK, see the line pressure diagnosis chart for line pressure concern causes.

7. When pressure tests are done, install the pressure tap plug.
- Tighten to 10 Nm (89 lb-in).

Line Pressure Diagnosis Chart: