FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Line Pressure Test

This test verifies that the line pressure is within specifications.

CAUTION: The transmission tester MUST BE REMOVED and the vehicle harness installed when verifying these procedures.

CAUTION: Perform Line Pressure Test prior to performing stall speed test. If line pressure is low at stall, do not perform Stall Speed Test or further transaxle damage will occur. DO NOT MAINTAIN WIDE OPEN THROTTLE in any gear range FOR MORE THAN FIVE SECONDS.

1. NOTE: The vehicle harness must be connected to the transaxle to verify these pressures.

Refer to Pinpoint Test E. E: Electronic Pressure Control (EPC) Solenoid
2. Connect pressure gauge to line pressure tap.

Line & EPC Pressure Ports:





3. Start engine and check line pressure.
4. If line pressure is not within specification, perform On-Board Diagnostic test and Pinpoint Test E. Perform air pressure checks and service main control system or pump as required.

Line Pressure Chart No. 401:





5. If the line pressure is not within specification after mechanical checks and there are no electrical codes, the Electronic Pressure Control (EPC) solenoid may be mechanically malfunctioning. Connect a pressure gauge to EPC pressure tap. Start engine and check EPC pressure. If pressures are not correct, replace EPC solenoid.