41TE NGC

P1776-SOLENOID SWITCH VALVE LATCHED IN LR POSITION







Theory of Operation

The Solenoid Switch Valve, an internal, hydraulically operated valve, controls the direction of the transmission fluid when the L/R solenoid is energized. When the solenoid switch valve is in the downshifted position and the L/R solenoid is energized, fluid is directed to the L/R element for 1st gear. When the solenoid switch valve is in a up shifted position (2nd, 3rd, and 4th gear) and the L/R solenoid is energized, fluid is directed into the Lockup Switch Valve which controls the Torque Converter Clutch. When doing PEMCC or FEMCC, the L/R pressure switch should indicate no pressure if the solenoid switch valve is in the L/R position. If the L/R pressure switch indicates pressure for some time while in partial or full EMCC, the EMCC operation is aborted and momentarily inhibited to avoid accidental application of the L/R clutch. EMCC is attempted again when there is no L/R pressure. The fourth detection of L/R pressure while in PEMCC or FEMCC will result in setting the DTC. Torque converter EMCC operation is inhibited after five minutes of substituted operation.

- When Monitored:
Every 7 ms when doing PEMCC or FEMCC.

- Set Condition:
Must be in partial or full EMCC. The DTC is set if L/R pressure is detected high for the fourth time.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. CHECK FOR RELATED DTCS
1. With the scan tool, check for other Transmission DTCs.

Is the DTC P0841 present also?

Yes

- P0841 Perform the appropriate diagnostic procedure.

No

- Go To 2

2. CHECK THE Event Data FOR TRS CODE TR2
1. With the scan tool, check the Event Data for P1776.

Does the Event Data show a TRS Code of TR2?

Yes

- This indicates the shift lever and the manual control valve were in the T2 transition zone between Neutral and OD. Check the shifter cable for: proper adjustment, binding, friction, improper routing, or the shifter was moved in transit. Repair as necessary.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Go To 3

3. CHECK IF THE DTC IS CURRENT
1. With the scan tool, check the Starts Since Set counter for P1776.

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

Is the status Active or is the Starts Since Set counter 2 or less for this DTC?

Yes

- Go To 4

No

- Go To 9

4. CHECK THE PCM AND WIRING USING THE TRANSMISSION SIMULATOR
1. Turn the ignition off to the lock position.
2. Remove the Ignition Switch Feed fuse from the TIPM.

CAUTION: Removal of the Ignition Switch Feed fuse from the TIPM will prevent the vehicle from being started in gear.

WARNING: The Ignition Switch Feed fuse must be removed from the TIPM. Failure to do so can result in possible serious or fatal injury.

3. Install the Transmission Simulator 8333A and the Electronic Transmission Adapter kit.

NOTE: Check connectors - Clean/repair as necessary.

4. Ignition on, engine not running.
5. With the Transmission Simulator, turn the Pressure Switch selector switch to L/R.
6. With the scan tool, monitor the L/R Pressure Switch State while pressing the Pressure Switch Test button.

Did the Pressure Switch state change from open to closed when the test button was pressed?

Yes

- Go To 8

No

- Go To 5

5. CHECK THE (T50) L/R PRESSURE SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off to the lock position.
2. Disconnect the Transmission Simulator.
3. Disconnect the PCM C4 harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the PCM Pinout Box 8815 to perform diagnosis.

4. Ignition on, engine not running.
5. With the scan tool in under TIPM, actuate the TCM output.
6. Measure the voltage of the (T50) L/R Pressure Signal circuit.

Is the voltage above 0.5 of a volt?

Yes

- Repair the (T50) L/R Pressure Signal circuit for a short to voltage.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Go To 6

6. CHECK THE (T50) L/R PRESSURE SIGNAL CIRCUIT FOR AN OPEN




1. Turn the ignition off to the lock position.
2. Measure the resistance of the (T50) L/R Pressure Signal circuit between the Transmission Solenoid/Pressure Switch Assembly harness connector and the appropriate terminal of the PCM Pinout Box 8815.

Is the resistance above 5.0 Ohms?

Yes

- Repair the (T50) L/R Pressure Signal circuit for an open.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Go To 7

7. CHECK THE (T50) L/R PRESSURE SIGNAL CIRCUIT FOR A SHORT TO GROUND




1. Measure the resistance between ground and the (T50) L/R Pressure Signal circuit.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (T50) L/R Pressure Signal circuit for a short to ground.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for Service Information Tune-ups or Service Bulletins for any possible causes that may apply. If no problems are found, replace and program the PCM. With the scan tool, perform Quick Learn Quick Learn Procedure.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

8. CHECK THE SOLENOID SWITCH VALVE FOR STICKING
1. Remove the transmission oil pan and Valve body and inspect the Solenoid Switch Valve for sticking in its bore, repair or replace as necessary.

NOTE: This DTC may be caused by debris lodged in the Transmission Solenoid Switch Valve bore. If debris is found, clean the valve body and reassemble the transmission.

2. With the scan tool, record the Event Data for P1776 and erase DTCs.
3. Reassemble the transmission and test drive the vehicle. Try to duplicate the original set conditions using the Event Data recorded earlier.
4. With the scan tool, check Transmission DTCs.

Did the DTC P1776 reset?

Yes

- Replace the Transmission Solenoid/Pressure Switch Assembly.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Test Complete
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

9. CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Test Drive the vehicle and verify if the transmission is launching in 2nd gear and/or there is no TCC engagement.
3. With the scan tool, check the EVENT DATA to help identify the conditions in which the DTC was set.
4. Check for any Service Information Tune-ups or Service Bulletins for possible causes that may apply.

Are there 2nd gear launches and/or no TCC engagement?

Yes

- Disassemble and inspect the Valve Body Inspect the Solenoid Switch Valve for sticking in its bore and repair or replace as necessary.
- Perform the 40/41TE TRANSMISSION VERIFICATION TEST. 40/41TE Transmission Verification Test.

No

- Test Complete.