Dodge Ram Truck 1500-2500-3500. Manual — part 1741

P1750-TRANSMISSION THROTTLE VALVE POSITION SENSOR CIRCUIT HIGH (CONTINUED)

4.

CHECK THE (K312) TTVA POSITION SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition off to the lock position.

Disconnect the ECM C1 and C2 harness connectors.

Ignition on, engine not running.

Measure the voltage of the (K312) TTVA Position Sensor Signal circuit.

Is the voltage above 0.5 volts?

Yes

>> Repair the (K312) TTVA Position Sensor Signal circuit for

a short to voltage.

Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/TRANSMISSION CONTROL MOD-
ULE - DIAGNOSIS AND TESTING)

No

>> Go To 5

5.

CHECK THE (K312) TTVA POSITION SENSOR SIGNAL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT

Measure the resistance between the (K312) TTVA Position Sensor
Signal circuit and all other circuits in the ECM C1 and C2 harness
connectors.

Is the resistance below 100 kohms between the (K312) TTVA
Position Sensor Signal circuit and any other circuit(s) in the
ECM C1 or C2 harness connectors.

Yes

>> Repair the (K312) TTVA Position Sensor Signal circuit for

a short to another circuit(s).

Perform RE TRANSMISSION VERIFICATION TEST VER -
1 (DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/TRANSMISSION CONTROL MOD-
ULE - DIAGNOSIS AND TESTING)

No

>> Go To 6

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1750-TRANSMISSION THROTTLE VALVE POSITION SENSOR CIRCUIT HIGH (CONTINUED)

6.

CHECK THE ECM OPERATION

Turn the ignition off to the lock position.

Reconnect all previously disconnected connectors.

Ignition on, engine not running.

With the scan tool, record and erase Engine DTCs.

Turn the ignition off to the lock position.

Disconnect the TTVA harness connector.

Ignition on, engine not running.

With the scan tool, read Engine DTCs.

Did the DTC Transmission Throttle Valve Position Sensor Circuit High set?

Yes

>> Using the schematics as a guide, check the Engine Control Module (ECM) pins, terminals, and connec-

tors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground cir-
cuits. If no problems are found, replace and program the ECM per the Service Information. (Refer to 8
- ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CONTROL MODULE - REMOVAL)

Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - DIAGNOSIS AND TEST-
ING)

No

>> Go To 7

7.

INTERMITTENT WIRING AND CONNECTORS

The conditions necessary set this DTC are not present at this time.

Use the Freeze Frame Data to help duplicate the conditions that set the DTC. Pay particular attention to the DTC
set conditions, such as, VSS, MAP, ECT, and Load.

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.

Refer to any 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.

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1751-TRANSMISSION THROTTLE VALVE POSITION MINIMUM RANGE
PERFORMANCE

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P1751-TRANSMISSION THROTTLE VALVE POSITION MINIMUM RANGE PERFORMANCE (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:
Ignition on and with or without engine running with transmission in the park or neutral position. Note: Not mon-
itored when either the engine is cranking or while vehicle is moving.

•

Set Condition:
Each time the ignition is cycled to the on position, the ECM commands a TTVA internal calibration procedure
(autozero) to determine the zero position. If the TTVA does not reach a calibrated minimum position in a pre-
determined amount of time, the DTC will set.

Possible Causes

TRANSMISSION THROTTLE VALVE ACTUATOR BINDING

TRANSMISSION THROTTLE VALVE COMPONENTS

TRANSMISSION THROTTLE VALVE ACTUATOR

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

Diagnostic Test

1.

CHECK IF THE DTC IS CURRENT

Ignition on, engine not running.

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 2

No

>> Go To 5

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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