P1776-SOLENOID SWITCH VALVE LATCHED IN LR POSITION





For a complete wiring diagram Refer to Section 8W.

Theory of Operation


The Solenoid Switch Valve (SSV) controls the direction of the transmission fluid when the L/R Solenoid is energized. The SSV will be in the downshifted position in 1st gear, thus directing the fluid to the L/R clutch circuit. In 2nd through 5th gears, it will be in the upshifted position and directing the fluid into the torque converter clutch (TCC).

When in 2nd, 2nd Prime, 3rd, 4th, or 5th gear, the Torque Converter Clutch (TCC) can be engaged when certain conditions are met. The TCC piston is electronically modulated by increasing the duty cycle of the L/R solenoid until the torque converter slip difference (difference between engine and transmission input speed) is within 60 RPM. Then the L/R solenoid is fully energized (FEMCC / 100% duty cycle). Torque converter slip is monitored in FEMCC to ensure adequate clutch capacity.


  • When Monitored:

    Continuously when performing partial or full EMCC - PEMCC or FEMCC.

  • Set Condition:

    If the transmission senses the L/R pressure switch closing while performing PEMCC or FEMCC. This DTC will set after two unsuccessful attempts to perform PEMCC or FEMCC. This DTC can take up to five minutes of problem identification before illuminating the MIL.


Possible Causes
  
RELATED DTC P0841 PRESENT
  
LR PRESSURE SWITCH SENSE CIRCUIT OPEN
  
LR PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
  
SOLENOID SWITCH VALVE
  
TRANSMISSION CONTROL MODULE
  
INTERMITTENT WIRING AND CONNECTORS
  

Always perform the 45RFE/545RFE Pre-Diagnostic Troubleshooting Procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)



Diagnostic Test

1.DETERMINING IF RELATED DTC'S ARE PRESENT



Is the DTC P0841 present also?

Yes
  • Refer to the Transmission category and perform the appropriate symptom.


No
  • Go To 2

2.CHECK TO SEE IF DTC P1776 IS CURRENT


NOTE: NOTE: This counter only applies to the last DTC set.



Is the STARTS SINCE SET counter 2 or less?

Yes
  • Go To 3


No
  • Go To 7

3.TCM AND WIRING



CAUTION: Removal of the Starter Relay will prevent the vehicle from being started in gear.


WARNING: The Starter Relay must be removed from the PDC. Failure to do so can result in personal injury or death.


NOTE: Failure to remove the Starter Relay can cause a Transmission - No Response condition.







Did the state of the LR Pressure Switch change while pressing the Pressure Switch Test button?

Yes
  • Go To 4


No
  • Go To 5

4.SOLENOID SWITCH VALVE




Were there any problems found?

Yes


No
  • Go To 7

5.LR PRESSURE SWITCH SENSE CIRCUIT OPEN








Is the resistance above 5.0 ohms?

Yes


No
  • Go To 6

6.(T50) LR PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND





Is the resistance below 5.0 ohms?

Yes


No
  • Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM per the Service Information. With the scan tool, perform QUICK LEARN.
  • Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)

7.INTERMITTENT WIRING AND CONNECTORS







Where there any problems found?

Yes


No
  • Test Complete.