When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
Set Condition:
A shorted condition is detected in the TIPM Transmission Control Output circuit.
Possible Causes
(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORTED TO POWER
TOTALLY INTEGRATED POWER MODULE (TIPM)
Diagnostic Test
1.CHECK IF THE DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, select View DTCs.
Is the status Active for this DTC?
Ye s>>
Go to 2
No>>
Go to 4
2.(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT SHORTED TO POWER
Turn the ignition off
Disconnect the TIPM C10 harness connector.
Disconnect the Transmission Solenoid harness connector.
Measure the voltage between the (T16) Transmission Control Output
circuit at the at the TIPM C10 harness connector and ground.
Is the voltage above 10.0 v?
Ye s>>
Repair the (T16) Transmission Control Output circuit for a
short to power.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go to 3
When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
Set Condition:
An open condition is detected in the TIPM on the Transmission Control Output circuit.
Possible Causes
(T16) TRANSMISSION CONTROL OUTPUT CIRCUIT OPEN
TOTALLY INTEGRATED POWER MODULE (TIPM)
Diagnostic Test
1.CHECK IF THE DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, select View DTCs.
Is the status Active for this DTC?
Ye s>>
Go to 2
No>>
Go to 4
2.CHECK THE (T16) TRANSMISSION CONTROL OUTPUT CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid harness connector.
Ignition on, engine not running.
Using the scan tool under the TIPM Actuators, actuate the Transmission
control output.
Using a 12-volt test light connected to ground, check the (T16) Trans-
mission Control Output circuit at the Transmission Solenoid harness
connector.
NOTE: The test light must illuminate brightly. Compare the bright-
ness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Ye s>>
Go To 3
No>>
Repair the (T16) Transmission Control Output circuit for an
open.
Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 21 - TRANSMISSION/TRANSAXLE/
AUTOMATIC - 48RE - STANDARD PROCEDURE)
3.TOTALLY INTEGRATED POWER MODULE
NOTE: Before continuing, check the TIPM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors.
Pay particular attention to allPower and voltage circuits.
Were any problems found?
Ye s>>
Repair as necessary.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Replace the Totally Integrated Power Module per Service Information.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
When Monitored:
With the ignition on. Battery voltage greater than 10 volts.
Set Condition:
An overcurrent condition is detected in the Transmission Control Output circuit. One Trip Fault. Three good
trips to turn off the MIL.
Possible Causes
SOLENOID/PRESSURE SWITCH ASSEMBLY
POWERTRAIN CONTROL MODULE (PCM)
TOTALLY INTEGRATED POWER MODULE (TIPM)
Diagnostic Test
1.CHECK IF THE DTC IS ACTIVE
Ignition on, engine not running.
With a scan tool, read TIPM DTCs.
Is the DTC active at this time?
Ye s>>
Go To 2
No>>
Go To 5
2.CHECK THE (T16) TRANSMISSION CONTROL OUTPUT CIRCUIT
Turn the ignition off.
Disconnect the TIPM C10 harness connector.
Connect the positive probe of an ammeter to battery positive and con-
nect the negative probe to the (T16) Transmission Control Output circuit
in the TIPM C10 harness connector.
Read the amperage on the ammeter.
Does the amperage read below 2.0 amps?
Ye s>>
Go To 4
No>>
Go To 3
P1740-TCC O/D SOL PERFORMANCE (GAS)
For a complete wiring diagramRefer to Section 8W
Theory of Operation
The Torque Converter Clutch (TCC) Solenoid is used to engage the TCC which improves fuel economy.
When Monitored:
The Torque Convertor Clutch (TCC) and Overdrive Clutch (OD) will be testedeach time the PCM requests
TCC engagement in 3rd gear and OD.
Set Condition:
The DTC will set if the expected RPM drop is not achieved while attempting toengage TCC or OD. This
indicates a malfunctioning torqueconvertor or overdrive clutch.
Possible Causes
ENGINE DTCS PRESENT
TRANSMISSION DTCS PRESENT
TRANSMISSION TEMPERATURE TOO COLD
OIL PAN CONTAINS EXCESSIVE DEBRIS
3-4 SHIFT SOLENOID
SHAFT OR SEAL DAMAGE
TCC SOLENOID
TORQUE CONVERTER
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
Diagnostic Test
1.ENGINE DTCS PRESENT
Ignition on, engine not running.
With the scan tool, read Engine DTCs.
Are there any Engine Temperature, Cam, Engine RPM, Misfire, P/N, or TPS DTC’s present?
Ye s>>
Refer to 9 - ENGINE ELECTRICAL DIAGNOSTICS - DIESEL and perform the appropriate symptom.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 2
2.CHECK FOR OTHER TRANSMISSION DTCS PRESENT
Are any of the DTCs P0720, P0973, P0974, P2769, and/or P2770, also present?
Ye s>>
Refer to the Transmission category, and perform the appropriate symptom(s).
No>>
Go To 3
3.CHECK IF THE DTC IS CURRENT
With the scan tool, read Engine DTCs.
Record the Freeze Frame data for the reported DTC.
With the scan tool, erase DTCs.
Turn the ignition off to the lock position.
Using the Freeze Frame data recorded earlier, try to duplicate the conditions in which the DTC originally set.
NOTE: It may be necessary to road test the vehicle to duplicate the originalset conditions.
With the scan tool, read Engine DTCs.
Did the DTC reset?
Ye s>>
Go To 4
No>>
Go To 14
4.VERIFY THE TOW/ HAUL OVERDRIVE FEATURE
NOTE: The transmission fluid temperature must be above 0.0° C (32° F) before proceeding.
With the scan tool, build a custom display using: Engine RPM, Output Shaft Speed, TCC Solenoid, O/D Solenoid
and TPS.
NOTE: This display will monitor the operation of the components.
Start the engine, turn off Overdrive or Tow Haul and test drive the vehicle.
Attain a steady speed of 88.5 Km/h or 55 MPH with a minimum of 1.15 volts throttle opening for 20 seconds.
NOTE: Check the Shift pattern as the vehicle upshifts to speeds of 88.5 Km/hor 55 MPH.
Is the Engine RPM within 60 RPM of the Output Shaft Speed RPM?
Ye s>>
Go To 10
No>>
Go To 5
5.CHECK IF THE OUTPUT SPEED IS GREATER THAN ENGINE RPM
In the previous test, is the Output Shaft Speed greater than Engine RPM?
Ye s>>
Go To 6
No>>
Go To 10
6.CALCULATE EXPECTED ENGINE RPM
With the scan tool, build a custom display using: Engine RPM, Output Shaft Speed, TCC Solenoid, O/D Solenoid
and TPS.
NOTE: This display will monitor the operation of the components.
Start the engine, turn off Overdrive or Tow Haul and test drive the vehicle.
Attain a steady speed of 88.5 Km/h or 55 MPH with a minimum of 1.15 volts throttle opening for 20 seconds.
With the scan tool, verify the 3-4 Solenoid (O/D) Solenoid is on and the TCC solenoid is locked
NOTE: Use this formula, Output Shaft Speed x 0.69 = expected Engine RPM.
Did the Engine RPM drop to 0.69 of the Output Shaft Speed RPM?
Ye s>>
Go To 10
No>>
Go To 7
7.GOVERNOR PRESSURE SYSTEM TEST
Turn the ignition off to the lock position.
Connect a 0 to 2068 kPa or 0 to 300 PSI pressure gauge to the Overdrive Clutch Test Port.
Connect a 0 to 2068 kPa or 0 to 300 PSI pressure gauge to the Governor Test Port.
Start the engine.
NOTE: Allow the transmission temperature to rise to normal operating temperature.
While observing both pressure gauges, select 4th Gear from Gov and 3-4 System Test.
NOTE: The Governor pressure should rise to above 137.8 kPa or 20 PSI, shortly after the OD pressure
should rise above 275.7 kPa or 40 PSI.
Did the pressures act as described?
Ye s>>
Go To 8
No>>
Go To 9
8.CHECK IF THE OIL PAN CONTAINS EXCESSIVE DEBRIS
Remove the transmission oil pan per the Service information.
Is the transmission fluid burnt or does the transmission oil pan contain excessive debris?
Ye s>>
Repair internal transmission as necessary. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC -
48RE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Go To 10
9.CHECK THE 3-4 SHIFT SOLENOID
Turn the ignition off to the lock position.
Replace the 3-4 Solenoid per the Service information. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC -
4 8 R E / VA LV E B O D Y - R E M O VA L )
Connect a 0 to 2068 kPa or 0 to 300 PSI pressure gauge to the Overdrive Clutch Test Port.
Connect a 0 to 2068 kPa or 0 to 300 PSI pressure gauge to the Governor Test Port.
Start the engine.
NOTE: Allow the transmission temperature to rise to normal operating temperature.
While observing both pressure gauges, select 4th gear from the Governor 3-4 shift valve system test.
NOTE: The Governor pressure should rise above 137.8 kPa or 20 PSI, shortly after the OD pressure should
rise above 275.7 kPa or 40 PSI.
Did the pressures act as described?
Ye s>>
Te s t C o m p l e t e .
No>>
Overhaul the transmission per the Service Information. Carefully inspect the seals and clutches related
to the OD Clutch. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE -REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
10.TORQUE CONVERTER CLUTCH
Turn the ignition on.
With the scan tool, perform the Torque Converter Clutch test.
Did the engine stall?
Ye s>>
Go To 11
No>>
Go To 13
11 .GOVERNOR/3-4 SHIFT VALVE
Start the engine.
Perform the Governor and 3-4 Shift Valve System Test, select 4th gear.
Did the engine stall?
Ye s>>
Go To 12
No>>
Go To 13
12.TCC SOLENOID
Replace the TCC Solenoid. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE/VALVE BODY -
REMOVAL)
With the scan tool, perform the Governor and 3-4 Solenoid test, select 4th gear.
Did the engine stall?
Ye s>>
Repair internal transmission as necessary. Check for blocked passages. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - REMOVAL)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Te s t C o m p l e t e .
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
13.SHAFT OR SEAL DAMAGE
Remove the Transmission Oil Pump per the Service information. (Refer to 21- TRANSMISSION/TRANSAXLE/AU-
TOMATIC - 48RE/OIL PUMP - DISASSEMBLY)
Inspect the Reaction shaft, Input Shaft and Input seal.
Are any of the parts damaged or worn?
Ye s>>
Repair as necessary, also replace the Torque Converter.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No>>
Replace the Torque Converter. NOTE: Inspect the Reaction Shaft, Input Shaft and Input Seal. Replace
as necessary if any of the parts are damaged or worn.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
Theory of Operation
The Governor Pressure Control System is used to regulate the governor pressure which controls the shifts for first,
second, and third gear. The Governor Pressure Control System test verifies that the requested pressure and the
actual pressure are within a predetermined tolerance.
When Monitored:
While driving and the commanded governor pressure is equal to the pressurerequired for third gear.
Set Condition:
If the governor pressure sensor output is less than 407 kPa (60 psi) or greater than 621 kPa (80 psi) when the
requested pressure is 407 - 621 kPa (60 - 80 psi) for 2.2 seconds. This DTC will set if there are two trips of
five consecutive bad 2.2 second tests with the transmission oil temperature between 23.5 - 88° C (74 - 190°
F).
Possible Causes
OTHER TRANSMISSION DTCS PRESENT
(F856) 5-VOLT SUPPLY CIRCUIT OPEN
(F856) 5-VOLT SUPPLY CIRCUIT OPEN - INTERNAL
GOVERNOR PRESSURE SENSOR
VA LV E B O D Y
INTERNAL TRANSMISSION
POWERTRAIN CONTROL MODULE
TRANSMISSION - INTERNAL DAMAGE
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
Diagnostic Test
1.CHECK IF OTHER TRANSMISSION DTCS ARE PRESENT
Ignition on, engine not running.
With the scan tool, read Engine DTCs.
Are any other transmission DTCs present?
Ye s>>
Refer to the Transmission category and perform the appropriate symptom(s). (Refer to 21 - TRANS-
MISSION/TRANSAXLE/AUTOMATIC - 48RE - DIAGNOSIS AND TESTING)
No>>
Go To 2
2.CHECK IF THE GOVERNOR PRESSURE IS ABOVE 3 PSI IN DRIVE
CAUTION: Apply the parking brake.
Start the engine and allow the transmission to reach normal operating temperature above 43° C (110° F).
CAUTION: Apply the brakes.
With the engine at idle, place the gear selector in Drive.
With the scan tool, read the Governor Pressure.
Is the Governor Pressure above 21 kPa (3 psi)?
Ye s>>
Go To 3
No>>
Go To 4