Dodge Ram Truck 1500-2500-3500. Manual — part 1742

P1751-TRANSMISSION THROTTLE VALVE POSITION MINIMUM RANGE PERFORMANCE (CONTINUED)

2.

CHECK TTVA FOR SIGNS OF DAMAGE

Turn the ignition off to the lock position.

Visually inspect the TTVA shaft for any signs of external damage or improperly mounted.

NOTE: It is not necessary to remove the TTVA to perform this procedure.

Is the TTVA damaged or improperly mounted?

Yes

>> Repair as necessary.

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 3

3.

CHECK THE TTVA POSITIONS WITH THE AUTO ZERO FEATURE

NOTE: Each time the ignition is cycled to the on position, the ECM commands a TTVA internal calibration
procedure (autozero) to determine the zero position. Do not press on the accelerator pedal during this test.
With the scan tool, monitor the TTVA position during the autozero test.

Ignition on, engine not running.

Is the TTVA position between 3 and 26 degrees after completion of the autozero test?

Yes

>> Go To 5

No

>> Go To 4

4.

CHECK THE TRANSMISSION THROTTLE VALVE

Turn the ignition off to the lock position.

Remove the TTVA from the transmission per the Service Information.

Properly support the TTVA and reconnect the TTVA wiring harness.

Like in the previous step, with the scan tool, monitor the TTVA position during the autozero test.

Ignition on, engine not running.

Is the TTVA position between 3 and 26 degrees after completion of the autozero test?

Yes

>> Repair internal transmission as necessary. Refer to the Service Information for proper repair procedures

for components related to the Transmission Throttle Valve.

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

No

>> Replace the TTVA per the Service Information.

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

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1751-TRANSMISSION THROTTLE VALVE POSITION MINIMUM RANGE PERFORMANCE (CONTINUED)

5.

INTERMITTENT WIRING AND CONNECTORS

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

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 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - DIAGNOSIS AND TEST-
ING)

No

>> Test Complete.

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1752-TRANSMISSION THROTTLE VALVE SPAN PERFORMANCE

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AUTOMATIC TRANSMISSION - 48RE - DIESEL - ELECTRICAL DIAGNOSTICS

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P1752-TRANSMISSION THROTTLE VALVE SPAN 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. After completion of the autozero procedure, the TTVA is instructed to
perform a span check to record the minimum and maximum span positions. This DTC will set if the minimum
total span is not achieved.

Possible Causes

TRANSMISSION THROTTLE VALVE ACTUATOR BINDING

TRANSMISSION THROTTLE VALVE

INTERNAL TRANSMISSION

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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