Line Pressure/EPC Pressure Test

This test verifies that the line pressure is within specification.





1. Connect pressure gauge to line pressure tap.
2. Start engine and check line pressures. Refer to Reference: Pressure Chart #401 to determine if line pressure is within specification.

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 transmission damage will occur. DO NOT MAINTAIN WOT in any transmission range FOR MORE THAN FIVE SECONDS.

CAUTION: Transmission tester MUST BE REMOVED from the transmission and the vehicle harness reinstalled to verify these pressures. Improper pressure readings may lead to improper parts replacement or internal damage.

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





4. Connect pressure gauge to EPC pressure tap.





5. Restart engine and check EPC pressure. Refer to Reference: Pressure Chart #401.

Line Pressure Test Chart:

6. If EPC pressure is not within specification, perform Pinpoint Test E to diagnose EPC operation. If EPC operation is OK, refer to Line Pressure Test Chart for line pressure concern causes.