P1751
DTC P1751
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P1751
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Shift Valve 1 Performance
Circuit/System Description
The shift solenoid (SS) 1 is part of the control solenoid valve assembly, which has no serviceable components. SS 1 provides fluid pressure to control the operation of the clutch select valve 2, which is located in the control valve lower body assembly. SS 1, in conjunction with clutch select valve 2, controls the pressure path to the reverse and low clutch and 4-5-6 clutch. A diagnostic test is performed by the transmission control module (TCM) to determine the state of the clutch select valve 2. During this diagnostic test, the TCM commands the SS 1 ON, supplying pressure to move the clutch select valve 2 toward its spring. At the same time, line pressure is elevated slightly to assist the spring side pressure. If the spring is broken, or the clutch select valve 2 cannot move due to another mechanical condition, the DTC will set.
Conditions for Running the DTC
* DTC P0101, P0102, P0103, P0106, P0107, P0108, P0171, P0172, P0174, P0175, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P042E, P0716, P0717, P0722, P0723, P0741, P0742, P1751, P2763, or P2764 is not set.
* Current gear is not 2nd.
* Engine speed is greater than 400 RPM for greater than 5 seconds.
* Ignition voltage is 8.6 volts or greater.
* Transmission fluid temperature (TFT) is 20-130°C (68-266°F).
* Calculated throttle position was 8 percent or greater, and has not dropped below 3 percent.
* Engine torque signal is valid.
* Throttle position sensor signal is valid.
* Engine torque is greater than 80 Nm (59 lb ft).
* Transmission input speed was 1200 RPM or greater and has not dropped below 900 RPM.
* Upshift or downshift is not in process.
Conditions for Setting the DTC
The TCM detects attained gear slip is 100 RPM or greater for 1 second.
Action Taken When the DTC Sets
DTC P1751 is a Type B DTC.
Conditions for Clearing the DTC
DTC P1751 is a Type B DTC.
Reference Information
Description and Operation
Transmission General Description Transmission General Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Engine idling in Park, with parking brake applied and drive wheels chocked.
2. Perform the Transmission Fluid Level and Condition Check Testing and Inspection to verify correct fluid level and condition.
3. Ignition ON, clear the TCM DTCs.
4. Perform the Road Test Initial Inspection and Diagnostic Overview. Verify the transmission operation performs as indicated in the road test instructions and that DTC P1751 did not set.
• If DTC P1751 sets
Refer to Circuit/System Testing below.
• If DTC P1751 did not set
5. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections.
Circuit/System Testing
1. Verify the transmission line pressures are within the range specified in the Line PC Solenoid Valve Pressure table. Refer to Line Pressure Check Line Pressure Check and Solenoid Valve Pressure Solenoid Valve Pressure.
• If line pressures are not within the specified ranges
Refer to Fluid Pressure High or Low Fluid Pressure High or Low.
• If line pressures are within the specified ranges
2. Ignition OFF, remove the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement Service and Repair.
3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test. A pressure change should occur for each solenoid valve.
• If a pressure change does not occur for each solenoid
Replace the Q8 control solenoid valve assembly.
• If a pressure change occurs for each solenoid
4. Listed in the chart below, are conditions for each component that could set DTC P1751. Carefully inspect each component for that condition. Repair or replace as necessary.
Repair Instructions
Note:
Perform the Reset Transmission Adapts Reset Transmission Adapts following all transmission related repairs.
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Valve Upper Body Assembly Cleaning and Inspection Control Valve Upper Body Assembly Cleaning and Inspection