Page 3217 of 5267

15.CHECK IF THE #5 AND/OR #7 CHECK BALL IS CUT OR DAMAGED
Turn the Ignition off to the lock position.
Remove the Valve Body Assembly per the Service Information.
Inspect the #5 and #7 check balls for any cuts or damage.
Inspect the 2C accumulator piston and seals and also the 2C tower seal on topof the valve body. Refer to the
Service Information.
Where there any problems found?
Ye s>>
Repair as necessary. Check for excessive clutch debris in the transmission oil pan. If excessive clutch
debris is present, repair 2C clutch as necessary. Refer to the Service Information for proper repair pro-
cedures.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
No>>
Go To 16
16.CHECK FOR EXCESSIVE FLUID LEAKAGE WITHIN THE 2C CLUTCH CIRCUIT
Air check the 2C Clutch hydraulic circuit. Refer to the Service Information.
NOTE: This hydraulic clutch circuit contains a small bleed orifice. Smallleakage is considered normal.
Was there excessive air leakage in the 2C Clutch hydraulic circuit?
Ye s>>
Repair as necessary. Refer to the Service Information.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1.
No>>
Replace the Transmission Solenoid/TRS Assembly per the Service Information. (Refer to 21 - TRANS-
MISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE/TRANS SOLENOID/TRS ASSY -REMOVAL)
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
Page 3218 of 5267
P0868-LINE PRESSURE LOW
For a complete wiring diagramRefer to Section 8W
Page 3219 of 5267

When Monitored:
Continuously while driving in a forward gear.
Set Condition:
The PCM continuously monitors Actual Line Pressure and compares it to DesiredLinePressure.IftheActual
Line Pressure is more than 10 psi below Desired Line Pressure, this DTC willset.
Possible Causes
CHECK FOR RELATED DTC’S
LOW FLUID LEVEL
(F856) 5-VOLT SUPPLY CIRCUIT OPEN
POOR LINE PRESSURE SENSOR CONNECTION
(F856) 5-VOLT SUPPLY CIRCUIT SHORT TO GROUND
(F856) 5-VOLT SUPPLY CIRCUIT SHORT TO VOLTAGE
(T118) PRESSURE CONTROL SOLENOID CONTROL CIRCUIT SHORT TO ANOTHER CIRCUIT
INTERNAL TRANSMISSION
LINE PRESSURE SENSOR
CRACKED, PLUGGED, OR MISINSTALLED PRIMARY OIL FILTER
STUCK OR STICKING MAIN REGULATOR VALVE
POWERTRAIN CONTROL MODULE
Always perform the 45RFE/545RFE Pre-Diagnostic Troubleshooting Procedure before proceeding. (Refer to
21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
Theory of Operation
Line pressure is measured by the Line Pressure Sensor (LPS) and regulationis achieved by changing the duty
cycle of the Pressure Control Solenoid (PCS) controlled by the Transmission Control System. (5% duty cycle =
solenoid off = Max line pressure, 62%duty cycle = solenoid on = Min line pressure). The Transmission Control
System calculates the desired line pressure based on inputs from both the engine and transmission.
The Transmission Control System calculates torque input to the transmission and uses it as the primary input to the
desired line pressure calculation. This is called Torque Based Line Pressure. In addition, the line pressure is set to
a preset level 827 or 931kPa (120 or 135 psi) during shifts and in Park and Neutral to ensure consistent shift qual-
ity. The desired line pressure is continuously being compared to the actual line pressure. If the actual line pressure
is consistently lower than the target while driving, the line pressure lowDTC P0868 will set.
Diagnostic Test
1.CHECKFORRELATEDDTCS
With the scan tool, check for other transmission DTCs
Is the DTC P0932 present also?
Ye s>>
Refer to the Transmission category and perform the appropriate symptom.
No>>
Go To 2
Page 3220 of 5267

2.CHECK IF THE DTC IS CURRENT
With the scan tool, check the STARTS SINCE SET counter for P0868.
NOTE: This counter only applies to the last DTC set.
Is the START SINCE SET COUNTER 2 or less?
Ye s>>
Go To 3
No>>
Go To 11
3.CHECK THE LINE PRESSURE SENSOR CONNECTION
Ignition on,engine not running.
With the scan tool, monitor the Line Pressure, firmly push the Line Pressure Sensor harness connector towards the
Transmission.
Did the Line Pressure change to about 207 kPa or 30 psi when the connector waspushed?
Ye s>>
Disconnect and properly reconnect the Line Pressure Sensor connector. Inspect terminals and repair as
necessary.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
No>>
Go To 4
4.CHECK THE PCM AND WIRING
Turn the ignition off to the lock position.
Remove the Ignition Switch Feed fuse from the TIPM.
CAUTION: Removal of the Ignition Switch Feed fuse from the TIPM will prevent the vehicle from being
startedingear.
WARNING: The Ignition Switch Feed fuse must be removed from the TIPM. Failure to do so can result in
personal injury or death.
Install the Transmission Simulator, Miller tool #8333.
With the Transmission Simulator select the
OFFposition on theInput/Output Speedswitch.
Ignition on, engine not running.
With the scan tool, monitor the Line Pressure during the following steps.
Using the Transmission Simulator, set the rotary knob to each of the 3 line pressure positions.
NOTE: All three scan tool Line Pressure readings should be steady and ± 14 kPa or 2.0 psi of the reading
specified on the Transmission Simulator.
Did the Line Pressure read within ± 14 kPa or 2.0 psi in all three positions?
Ye s>>
Go To 5
No>>
Go To 7
Page 3221 of 5267

5.CHECK THE LINE PRESSURE SENSOR
Turn the ignition off to the lock position.
Disconnect the Transmission Simulator, Miller tool #8333 and reconnect all previously disconnected connectors.
Install the Line Pressure Adaptor, Miller tool #8259, and the Pressure Gauge, Miller tool #C-3293, 0 to 2000 kPa or
0to300psi.
Start the engine in park.
Monitor the line pressure readings of both the scan tool and the pressure gauge and compare the two readings.
Is the line pressure gauge reading within 34 kPa or 5 psi of the scan tool reading?
Ye s>>
Go To 6
No>>
Replace the Line Pressure Sensor per the Service Information.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
6.CHECK FOR A PLUGGED TRANSMISSION OIL FILTER
Turn the ignition off to the lock position.
Remove and inspect the Transmission Oil Pan for excessive debris per the Service Information.
Remove and inspect the Primary Oil Filter per the Service Information.
NOTE: Make sure the Primary Transmission Oil Filter and/or O-ring is not cracked or split.
Does the Oil Pan contain excessive debris and/or is the Primary Oil Filter cracked or plugged?
Ye s>>
Repair the plugged, cracked, or split Primary Transmission Oil Filter and/or O-ring. If the Primary Trans-
mission Oil Filter is plugged refer to the Service Information for the proper Hydraulic repair procedure.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
No>>
Repair internal transmission and inspect the Transmission Oil Pump per the Service Information and
replace if necessary. If no problem is found, replace the Solenoid/TRS Assembly.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
7.CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
Disconnect the Transmission Simulator, Miller tool #8333.
Reconnect all previously disconnected connectors except the Line Pres-
sure Sensor harness connector.
Ignition on, engine not running.
Measure the voltage of the (F856) 5-volt Supply circuit in the Line Pres-
sure Sensor harness connector.
Is the voltage above 5.5 volts?
Ye s>>
Repair the (F856) 5-volt Supply circuit for a short to voltage.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PRO-
CEDURE)
No>>
Go To 8
Page 3222 of 5267

8.CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Disconnect the PCM C1 harness connector and connect Miller tool
#8815.
CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller tool #8815 to per-
form diagnosis.
Measure the resistance of the (F856) 5-volt Supply circuit between the
Line Pressure Sensor harness connector and the appropriate terminal
of Miller tool #8815.
Is the resistance above 5.0 ohms?
Ye s>>
Repair the (F856) 5-volt Supply circuit for an open.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PRO-
CEDURE)
No>>
Go To 9
9.CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND
Measure the resistance between ground and the (F856) 5-volt Supply
circuit.
Is the resistance below 5.0 ohms?
Ye s>>
Repair the (F856) 5-volt Supply circuit for a short to ground.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PRO-
CEDURE)
No>>
Go To 10
Page 3223 of 5267

10.CHECK THE (T118) PRESSURE CONTROL SOLENOID CONTROL CIRCUIT FOR A SHORT TO
ANOTHER CIRCUIT
Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid/TRS Assembly harness connec-
tor.
Disconnect all PCM harness connectors.
Measure the resistance between the (T118) Pressure Control Solenoid
Control circuit and all other circuits in the Transmission Solenoid/TRS
Assembly harness connector.
Is the resistance below 5.0 ohms between the (T118) Pressure
Control Solenoid Control circuit and any other circuit(s) in the
Transmission Solenoid/TRS Assembly harness connector?
Ye s>>
Repair the (T118) Pressure Control Solenoid Control circuit
for a short to another circuit(s).
Perform 45RFE/545RFE TRANSMISSION VERIFICATION
TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PRO-
CEDURE)
No>>
Using the schematics as a guide, check the Powertrain Control Module (PCM)terminals for corrosion,
damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems
are found, replace the PCM per the Service Information. With the scan tool,perform QUICK LEARN.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
11 .INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specifictothiscircuit.
Wiggle the wires while checking for shorted and open circuits.
With the scan tool, check the DTC EVENT DATA to help identify the conditionsin which the DTC was set.
Where there any problems found?
Ye s>>
Repair as necessary.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
Page 3224 of 5267
P0869-LINE PRESSURE HIGH
For a complete wiring diagramRefer to Section 8W