my brothers truck has the code p1754 i looked up the code and it says 1754 coast clutch soelenoid malfuction has anybody had this code before what should we check thanks
truck is an 06 with the automatic transmission
Your definition is incorrect
It should read
P1754-TRANSMISSION THROTTLE VALVE ACTUATOR STUCK
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 throttle 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.
Set Condition:
The monitored TTVA position sensor does not indicate a change in position when the TTVA is commanded to change the position.
Possible Causes
(F856) 5 VOLT SUPPLY CIRCUIT OPEN
(K314) TTVA MOTOR (+) CIRCUIT OPEN
(K315) TTVA MOTOR (-) CIRCUIT OPEN
(K314) TTVA MOTOR (+) CIRCUIT SHORT TO GROUND
(K315) TTVA MOTOR (-) CIRCUIT SHORT TO GROUND
(K314) TTVA MOTOR (+) CIRCUIT SHORT TO VOLTAGE
(K315) TTVA MOTOR (-) CIRCUIT SHORT TO VOLTAGE
(K314) TTVA MOTOR (+) CIRCUIT SHORT TO ANOTHER CIRCUIT
(K315) TTVA MOTOR (-) CIRCUIT SHORT TO ANOTHER CIRCUIT
TRANSMISSION THROTTLE VALVE COMPONENTS
TRANSMISSION THROTTLE VALVE ACTUATOR
ENGINE CONTROL MODULE
Did the DTC reset?
Yes
Go To 2
No
Go To 16
2. 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.
1. With the scan tool, monitor the TTVA position during the autozero test.
2. Ignition on, engine not running.
3. After the autozero test is completed, record the position percentage value.
4. Press and hold the accelerator pedal to full throttle after completion of the autozero test and record.
5. Subtract the TTVA full throttle value from the value recorded after the autozero test.
Is the difference between the two values greater than or equal to 48 degrees?
Yes
Go To 16
No
Go To 3
3. CHECK TTVA FOR SIGNS OF DAMAGE
1. Turn the ignition off to the lock position.
2. 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.
3.
Is the TTVA damaged or improperly mounted?
Yes
Repair as necessary.
Go To 4
4. CHECK THE TTVA POSITIONS WITH THE TTVA REMOVED
1. Turn the ignition off to the lock position.
2. Remove the TTVA from the transmission per the Service Information. (Refer to 21 - Transmission and Transfer Case/Automatic - 48RE/ACTUATOR, Throttle Valve - Removal)
NOTE: Check connectors - Clean/repair as necessary.
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.
3. Properly support the TTVA and reconnect the TTVA wiring harness.
4. With the scan tool, monitor the TTVA position during the autozero test.
5. Ignition on, engine not running.
6. After the autozero test is completed, record the position percentage value.
7. After recording the position percentage value, press and hold the accelerator pedal to full throttle and note position percentage value.
8. Subtract the TTVA full throttle value from the value recorded after the autozero test.
Is the difference between the two values greater than or equal to 48 degrees?
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 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Go To 5
5. CHECK THE TTVA
1. Turn the ignition off to the lock position.
2. Disconnect the TTVA harness connector
3. Connect a 12-volt test light between the (K314) TTVA Motor (+) circuit and the (K315) TTVA Motor (-) circuit in the TTVA harness connector.
4. Monitor the test light in the following step.
NOTE: The test light should momentarily flash brightly, one time, immediately after the ignition is turned to the on position.
5. Ignition on, engine not running.
Did the test light illuminate brightly one time after turning the ignition to the on position?
Yes
Go To 6
No
Go To 7
6. CHECK THE (K315) TTVA MOTOR (-) CIRCUIT FOR A SHORT TO GROUND
Measure the resistance between ground and the (K315) TTVA Motor (-) circuit.
Is the resistance below 5. 0 ohms?
Yes
Repair the (K315) TTVA Motor (-) circuit for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Replace the TTVA per the Service Information (Refer to 21 - Transmission and Transfer Case/Automatic - 48RE/ACTUATOR, Throttle Valve - Removal)
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
7. CHECK THE (F856) 5 VOLT SUPPLY CIRCUIT FOR AN OPEN
1. Turn the ignition off to the lock position.
2. Disconnect the ECM C1 and C2 harness connectors.
3. Measure the resistance of the (F856) 5-volt Supply circuit between the ECM C2 harness connector and the TTVA harness connector.
Is the resistance below 5. 0 ohms?
Yes
Go To 8
No
Repair the (F856) 5-volt Supply circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
8. CHECK THE (K314) TTVA MOTOR (+) CIRCUIT FOR AN OPEN
1. Measure the resistance of the (K314) TTVA Motor (+) circuit between the ECM C1 harness connector and the TTVA harness connector.
Is the resistance below 5. 0 ohms?
Yes
Go To 9
No
Repair the (K314) TTVA Motor (+) circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
9. CHECK THE (K315) TTVA MOTOR (-) CIRCUIT FOR AN OPEN
1. Measure the resistance of the (K315) TTVA Motor (-) circuit between the ECM C1 harness connector and the TTVA harness connector.
Is the resistance below 5. 0 ohms?
Yes
Go To 10
No
Repair the (K315) TTVA Motor (-) circuit for an open.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
10. CHECK THE (K314) TTVA MOTOR (+) CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the (K314) TTVA Motor (+) circuit.
Is the resistance below 5. 0 ohms?
Yes
Repair the (K314) TTVA Motor (+) circuit for a short to ground.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Go To 11
11. CHECK THE (K314) TTVA MOTOR (+) CIRCUIT FOR A SHORT TO VOLTAGE
1. Ignition on, engine not running.
2. Measure the voltage of the (K314) TTVA Motor (+) circuit.
3.
Is the voltage above 0. 5 volts?
Yes
Repair the (K314) TTVA Motor (+) circuit for a short to voltage.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Go To 12
12. CHECK THE (K315) TTVA MOTOR (-) CIRCUIT FOR A SHORT TO VOLTAGE
1. Measure the voltage of the (K315) TTVA Motor (-) circuit.
Is the voltage above 0. 5 volts?
Yes
Repair the (K315) TTVA Motor (-) circuit for a short to voltage.
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Go To 13
13. CHECK THE (K314) TTVA MOTOR (+) CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Turn the ignition off to the lock position.
2. Measure the resistance between the (K314) TTVA Motor (+) circuit and every other circuit in the ECM C1 and C2 harness connectors
Is the resistance below 5. 0 ohms between the (K314) TTVA Motor (+) circuit and any other circuit in the ECM C1 and C2 harness connectors?
Yes
Repair the (K314) TTVA Motor (+) for a short to another circuit(s).
Perform RE TRANSMISSION VERIFICATION TEST VER - 1 (DIESEL). (Refer to 28 - DTC-Based Diagnostics/MODULE, Transmission Control (TCM) - Standard Procedure)
No
Go To 14
14. CHECK THE (K315) TTVA MOTOR (-) CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Measure the resistance between the (K315) TTVA Motor (-) circuit and every other circuit in the ECM C1 and C2 harness connectors
Is the resistance below 5. 0 ohms between the (K315) TTVA Motor (-) circuit and any other circuit in the ECM C1 and C2 harness connectors?
Yes
Repair the (K315) TTVA Motor (-) for a short to another circuit(s).
Attention: TDR Forum Junkies 
