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5R55N Line Pressure Test
The line pressure tap is used to verify output pressure from Pressure Control (PCA(pos.3) or PCB(pos.10)) by turning
either one off while verifying the output from the solenoid. The second pressure tap is used to verify
the output from PCC solenoid.
This test verifies that the line pressure is within specifications.
1. Connection point (PCA or PCB).
2. Start engine and check line pressures, see below.
3. If pressures are not of range, check pressure on PCC port.
S-Type 3.0 Ltr, 4.0 Ltr:
Level in P/N: Idle -PC C=5, WOT Stall -PC C=5, Idle Line=125-165, WOT Stall Line=N/A
Level in R: Idle -PC C=116, WOT Stall -PC C=116, Idle Line=110-150, WOT Stall Line=290-360
Level in D/4: Idle -PC C=115, WOT Stall -PC C=115, Idle Line=110-150, WOT Stall Line=210-260
Level in 3: Idle -PC C=5, WOT Stall -PC C=5, Idle Line=N/A, WOT Stall Line=N/A
Level in 2: Idle -PC C=5, WOT Stall -PC C=5, Idle Line=N/A, WOT Stall Line=N/A
If the line pressure is not within the specifications, check PC C pressure.
Connect the pressure gauge as illustrated to PCC. Start engine, check pressures. See above specifications,
and verify that the pressure is within its parameter.
Note, is the electrical, electronic side is without malaise, then pursue the list down below which designates
itself to possible mechanical failures.
Test Results and Possible Causes
High at Idle- All Ranges:
Wiring Harnesses, EPC Boost Valve, EPC Solenoid, Main Regulator Valve
Low at Idle- All Ranges:
Low Fluid Level, Fluid Inlet Filter/Seal, Main Control Body, Cross Leaks, Gaskets, Pump, Separator Plate
Low - All Forward Ranges:
Forward Clutch, Main Control Body, Overdrive Servo, Intermediate Servo
Low in Park Only:
Valve Body
Low In Reverse Only:
Separator Plate, Rear Servo Piston, Cover Seal, reverse Clutch, Overdrive Servo, Intermediate Servo,
Valve Body, Forward Clutch
Low in Neutral Only:
Valve Body, Overdrive Servo, Intermediate Servo
Low in D Only:
Forward Clutch, Overdrive Servo, Intermediate Servo, Valve Body
Low in 4 Only:
Forward Clutch, Overdrive Servo, Intermediate Servo, Valve Body
Low in 2nd Position Only:
Intermediate Servo, Overdrive Servo, Forward Clutch
Statistic: Known Issues
7x Main Control Valve Body (PC A,B,C (see Valve Body picture pos. 3,6,10,14)).
Wear (pressure loss) at 3 PC valves can be greater than at the servo bore holes when added together.
6x Intermediate Servo (1 bore)
6x overdrive Servo (1 bore)
5x Forward Clutch
General Service Information
General Service InformationRear axle
Rear sub-frameFront axle
Lower ball-point joint, Shock absorber bushes, Stabilizer bar links + mountsBrake disc and pads
Engine
Intake Manifold / Ignition Coils / Spark-plugs/ engine-block ventilation (elbow)Injectors
Starter system
Valve clearance, timing-chain, tensioner and glides:
With valve clearance in its tolerance,
there was no need to take the camshafts down, so tensioners and co. have to wait, the good thing is the
tensioner pumps up in 3-4 min. the rattle noise disappears.
Cruise control malfunction, emergency mode
Automatic Transmission 5R55N
Info, tips, Fail Safe ModeStall Speed Test procedure and diagnoses
Valve Body, known issues
Valve Body, Solenoid test procedures
Line Pressure Test
Self made press for pressing down clutch drum springs, checking clutch tolerance without a dial gauge
Chassis
Air ConditioningMiscellaneous repairs
Wind-shield-wiper mechanism:
Time on the lot took its toll, wind-shield-wiper shafts had seized,
uninstalled the mechanism, freed the seized shafts through the use of a good rust loosener, heat, force.
Water in Spark-plug wells 3-2 cylinder:
After days of heavy rain the engine began to misfire with
accounted trouble codes, spark-plug wells were wet, an ionized rusty red path on the ceramic insulator had developed which shorted the
HV ignition spark.
Radio:
Connected the radio controls to the multi-functional steering wheel using
an analog digital converter.