Dodge Ram Truck 1500-2500-3500. Manual — part 1705
P0783-3-4 SHIFT SOL, NO RPM DROP AT LOCKUP (GAS) (CONTINUED)
3.
CHECK THE GOVERNOR AND OVERDRIVE PRESSURE
Turn the ignition off to the lock position.
Connect a 0 - 2068 KPa (0 - 300 PSI) pressure gauge to the Overdrive Clutch test port.
Connect another 0 - 2068 KPa (0 - 300 PSI) pressure gauge to the Governor Pressure test port. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - DIAGNOSIS AND TESTING)
Start the engine and allow the transmission temperature to rise to normal operating temperature.
CAUTION: Apply the parking brake.
Firmly apply the brakes and place the gear selector in Drive.
While observing the pressure gauges, with the scan tool, select 4th gear from the Gov and 3-4 Shift Valve Test.
NOTE: The governor pressure should rise above 138 kPa (20 PSI). Shortly after the O/D pressure should
rise above 276 kPa (40 PSI).
Did the pressures act as previously described?
Yes
>> Go To 4
No
>> Go To 5
4.
CHECK THE TRANSMISSION OIL CONDITION
Turn the ignition off to the lock position.
Remove the transmission oil pan and inspect for excessive debris and burnt oil.
Is the oil burnt or does the transmission oil pan contain excessive debris?
Yes
>> Repair the transmission as necessary. Refer to the Service Informtion for the proper repair procedures.
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - DIAGNOSIS AND TESTING)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
>> Go To 6
5.
CHECK THE GOVERNOR AND OVERDRIVE PRESSURE AFTER REPLACEMENT OF THE 3-4 SHIFT
SOLENOID
Turn the ignition off to the lock position.
Replace the 3-4 Shift Solenoid per the Service Information. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 48RE/VALVE BODY - DISASSEMBLY)
With the pressure gauges still attached, start the engine and allow the transmission temperature to rise to normal
operating temperature.
CAUTION: Apply the parking brake.
Firmly apply the brakes and place the gear selector in Drive.
While observing the pressure gauges, with the scan tool, select 4th gear from the Gov and 3-4 Shift Valve Test.
NOTE: The governor pressure should rise to above 138 kPa (20 PSI). Shortly after the O/D pressure should
rise above 276 kPa (40 PSI).
Did the pressures act as previously described?
Yes
>> Test Complete.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
>> Overhaul the transmission per the Service Informtion. Pay attention to seals and clutches related to the
OD clutch.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
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AUTOMATIC TRANSMISSION - 48RE - GAS - ELECTRICAL DIAGNOSTICS
DR/DH
P0783-3-4 SHIFT SOL, NO RPM DROP AT LOCKUP (GAS) (CONTINUED)
6.
INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Use the Freeze Frame Data to help duplicate the conditions in which the DTC originally set. Pay particular attention
to the DTC set conditions, such as, VSS, MAP, ECT, and Load
The vehicle must be driven (road load) to set this code. Drive the vehicle 4 times from 0 to 89 kmh (0 to 55
MPH) with a constant 20 % throttle position through all gears. Stop the vehicle, shut the engine off and then
repeat the procedure.
Using the schematics as a guide, visually inspect the related wiring harness. Look for any chafed, pierced, pinched,
or partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
Wiggle the wiring and connectors while checking for any possible open or shorted circuits.
Check for any Service Information Tune-ups or Technical Service Bulletins that may apply.
Were there any problems found?
Yes
>> Repair as necessary.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
No
>> Test Complete.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (GAS). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)
DR/DH
AUTOMATIC TRANSMISSION - 48RE - GAS - ELECTRICAL DIAGNOSTICS
21 - 753
P1740-TCC O/D SOL PERFORMANCE (GAS)
For the Transmission circuit diagram (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 48RE - SCHE-
MATICS AND DIAGRAMS)
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 tested each 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 to engage TCC or OD. This
indicates a malfunctioning torque convertor 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?
Yes
>> 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?
Yes
>> 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 3
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AUTOMATIC TRANSMISSION - 48RE - GAS - ELECTRICAL DIAGNOSTICS
DR/DH
P1740-TCC O/D SOL PERFORMANCE (GAS) (CONTINUED)
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 original set conditions.
With the scan tool, read Engine DTCs.
Did the DTC reset?
Yes
>> 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/h or 55 MPH.
Is the Engine RPM within 60 RPM of the Output Shaft Speed RPM?
Yes
>> 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?
Yes
>> 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?
Yes
>> Go To 10
No
>> Go To 7
DR/DH
AUTOMATIC TRANSMISSION - 48RE - GAS - ELECTRICAL DIAGNOSTICS
21 - 755
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