40/41TE Automatic Transaxle (NGC)

P1775-SOLENOID SWITCH VALVE LATCHED IN TCC POSITION





For a complete wiring diagram Consult Diagrams/Electrical.

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 the up shift 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 shifting into 1st gear, a special sequence is followed to insure solenoid switch valve movement into the downshifted position. The L/R pressure switch is monitored to confirm switch valve movement. If the solenoid switch valve movement is not confirmed (i.e. no L/R pressure when the L/R solenoid is energized), 2nd gear is substituted for 1st. No 1st gear (2nd gear is substituted). The transmission Torque converter FEMCC operation is inhibited. MIL on after 5 min. of substituted operation.

- When Monitored:
Prior to a shift into 1st gear.

- Set Condition:
Transmission temperature must be hot. DTC is set after six unsuccessful attempts to shift into 1st gear.





Always perform the 40/41TE Pre-Diagnostic Troubleshooting procedure before proceeding. Testing and Inspection

Diagnostic Test

1. DETERMINING IF RELATED DTCS ARE PRESENT
With the scan tool, check for other Transmission DTCs.
Is the DTC P0841 present also?

Yes

- Diagnose and repair the DTC(s).

No

- Go to 2

2. CHECK TO SEE IF DTC P1775 IS CURRENT
With the scan tool, view DTCs.
Is the status Active for this DTC or is the STARTS SINCE SET counter 2 or less?

Yes

- Go to 3

No

- Go to 8

3. CHECK THE PCM AND WIRING
Turn the ignition off to the lock position.
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 personal injury or death.

Install the Transmission Simulator, Miller tool #8333 and the Electronic Transmission Adapter kit.
Ignition on, engine not running.
With the Transmission Simulator, turn the Pressure Switch selector switch to L/R.
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

- Repair internal transmission as necessary. Inspect the Solenoid Switch Valve and repair or replace as necessary. If no problems are found, replace the Transmission Solenoid/Pressure Switch Assembly.
- Perform 40/41TE VERIFICATION TEST 40/41TE Transmission Verification Test

No

- Go to 4

4. (T16) TRANSMISSION CONTROL OUTPUT CIRCUIT OPEN




Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid/Pressure Switch Assembly harness connector.
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 Miller Special Tool #8815 to perform diagnosis.

Ignition on, engine not running.
With the scan tool in the TIPM, actuate the TCM output.
Using a 12-volt test light connected to ground, check all (T16) Transmission Control Output circuits in the appropriate terminals of Miller tool #8815.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly on all Transmission Control Output circuits?

Yes

- Go to 5

No

- Repair the (T16) Transmission Control Output circuit for an open.
- Perform 40/41TE VERIFICATION TEST 40/41TE Transmission Verification Test

5. (T50) L/R PRESSURE SIGNAL CIRCUIT SHORT TO VOLTAGE




Ignition on, engine not running.
While still actuating the TCM output in the TIPM with the scan tool, measure the voltage of the (T50) L/R Pressure Signal circuit.
Is the voltage above 0.5 volts?

Yes

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

No

- Go to 6

6. (T50) L/R PRESSURE SIGNAL CIRCUIT OPEN




Stop the TCM output actuation and turn the ignition off to the lock position.
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 Miller tool #8815.
Is the resistance above 5.0 ohms?

Yes

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

No

- Go to 7

7. (T50) L/R PRESSURE SIGNAL CIRCUIT SHORT TO GROUND




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

8. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Test drive and verify if the transmission is launching in 2nd gear and/or no TCC engagement.
With the scan tool, check the DTC EVENT DATA to help identify the conditions in which the DTC was set.
Are there 2nd gear launches and/or no TCC engagement?

Yes

- Disassemble and inspect the Valve Body and repair or replace as necessary. If no problems are found in the Valve Body, replace the Transmission Solenoid Pressure Switch Assembly.
- Perform 40/41TE VERIFICATION TEST 40/41TE Transmission Verification Test

No

- Test Complete.