Ford Fusion: Automatic Transmission - 6-Speed Automatic Transmission – 6F35 / Transmission Line Pressure Test. Diagnosis and Testing
Line Pressure Test
NOTE:
Perform the line pressure test prior to performing the stall
speed test. If the line pressure is low at stall, do not perform the
stall speed test or transmission damage will occur. Do not maintain WOT in any transmission range for more than 5 seconds.
This test verifies the line pressure is within specification.
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Remove the 2 bolts and position aside the air cleaner top assembly.
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Remove the air cleaner bottom assembly.
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Connect the air cleaner bottom assembly to the air cleaner top assembly.
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Connect the transmission fluid pressure gauge (307-004) to the line pressure tap.
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Start the engine and check the line pressure.
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Compare LINEDSD# to actual measured pressure. Actual
measured pressure should be within 10 PSI (69 kPa). Raise engine RPM to
2000 RPM, Verify LPC operation by monitoring LINE pressure while commanding LINEDSD# up and down.
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If the line pressure is not within specification, see the Line Pressure Diagnosis Chart for possible source.
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When the pressure tests are complete, install the line pressure tap plug.
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Torque: 18 Nm (159 lb-in).
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Disconnect the air cleaner bottom assembly from the air cleaner top assembly.
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Install the air cleaner bottom assembly.
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Position back the air cleaner top assembly and install the 2 bolts.
Line Pressure Diagnosis Chart
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Test Results
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Possible Source
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HIGH at IDLE
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Wiring Harnesses (open circuit/high resistance to LPC) LPC solenoid mechanically stuck ON
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Verify LPC operation by monitoring LINE pressure while commanding LINEDSD# up and down
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Main pressure regulator valve stuck in default position
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LOW at IDLE
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Low Transmission Fluid level
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LPC solenoid mechanically stuck OFF
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Verify LPC operation by monitoring LINE pressure while commanding LINEDSD# up and down
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Fluid Inlet Filter/Seal
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Main pressure regulator valve stuck in spring compressed position
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Broken or missing main pressure regulator valve spring
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Pump
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Transmission Air Pressure Test
Item
Description
1
Foward clutch
2
Direct clutch
3
Intermediate clutch
4
Low reverse clutch
5
Overdrive clutch
NOTE:
The center support contains an air bleed for the forward and
Low reverse clutch circuits...
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...
Other information:
Removal
NOTE:
Removal steps in this procedure may contain installation details.
Reversing lamp assembly
Remove the push pins.
Position aside the liftgate trim panel.
Remove the rear lamp assembly...
Removal
NOTE:
When removing any turbocharger air intake system components,
make sure to cover any open ports to prevent debris from entering the
system. The turbocharger compressor vanes can be damaged by even the
smallest particles. All components need to be inspected and cleaned
prior to installation or reassembly...