Dodge Ram Truck 1500-2500-3500. Manual — part 1738

P1740-TCC O/D SOL PERFORMANCE (DIESEL) (CONTINUED)

10.

TORQUE CONVERTER CLUTCH

Turn the ignition on.

With the scan tool, perform the Torque Converter Clutch test.

Did the engine stall?

Yes

>> 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?

Yes

>> 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?

Yes

>> 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 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

No

>> Test Complete.

Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (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?

Yes

>> Repair as necessary, also replace the Torque Converter.

Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (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 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1740-TCC O/D SOL PERFORMANCE (DIESEL) (CONTINUED)

14.

INTERMITTENT WIRING & 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

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 (DIESEL). (Refer to 21 - TRANSMISSION/
TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

No

>> Test Complete.

DR/DH

AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1749-TRANSMISSION THROTTLE VALVE POSITION SENSOR CIRCUIT LOW

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1749-TRANSMISSION THROTTLE VALVE POSITION SENSOR CIRCUIT LOW (CONTINUED)

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 transmission throttle valve cable has been replace by the transmission throttle valve actuator (TTVA). The TTVA
consists of an electric DC motor, two potentiometers, and a gear drive system. The TTVA is mechanically connected
to the transmission throttle valve in the valve body by the “D” shaped opening in the bottom of the TTVA shaft.

The Transmission Throttle Valve Actuator (TTVA) does not require any mechanical adjustments. All changes in throt-
tle valve position are controlled by the Engine Control Module (ECM).

The TTVA does require an initialization period after the actuator has been removed or replaced. After the actuator
has been removed or replaced, move the ignition to the ON position for thirty (30) seconds. This will allow the ECM
sufficient time to perform the internal calibration procedures to learn the TTVA’s current “zero” position.

•

When Monitored:
Continuously with the ignition on.

•

Set Condition:
When the Engine Control Module (ECM) detects the monitored Transmission Throttle Valve Position Sensor
voltage drops below a predetermined value.

Possible Causes

(K312) TTVA POSITION SENSOR SIGNAL CIRCUIT OPEN

(K312) TTVA POSITION SENSOR SIGNAL CIRCUIT SHORT TO GROUND

(K312) TTVA POSITION SENSOR SIGNAL CIRCUIT SHORT TO ANOTHER CIRCUIT

(F856) 5 VOLT SUPPLY CIRCUIT OPEN

(F856) 5 VOLT SUPPLY CIRCUIT SHORT TO GROUND

(F856) 5 VOLT SUPPLY CIRCUIT SHORT TO ANOTHER CIRCUIT

TRANSMISSION THROTTLE VALVE ACTUATOR

ENGINE CONTROL MODULE

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 48RE - STANDARD PROCEDURE)

DR/DH

AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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