P1776 Jeep OBD Code Diagnostic Procedure

P1776 Jeep OBD Code Definition:

SOLENOID SWITCH VALVE LATCHED IN LR POSITION

For a complete wiring diagram Refer to Section 8W.

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-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 inhibited. MIL on after 5 min. 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.

Possible Causes

RELATED DTC P0841 PRESENT

DTC EVENT DATA SHOWS TRS CODE TR2 – SHIFT LEVER OR MANUAL CONTROL VALVE IN A INVALID POSITION

SHIFTER CABLE OUT OF ADJUSTMENT

SOLENOID SWITCH VALVE STICKING IN ITS BORE

(T50) L/R PRESSURE SWITCH SENSE CIRCUIT OPEN

(T50) L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND

(T50) L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE

VALVE BODY

POWERTRAIN CONTROL MODULE

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC
– 42RLE – STANDARD PROCEDURE)

Diagnostic Test

1. DETERMINING IF RELATED DTC’S ARE PRESENT

With the scan tool, check for other Transmission DTCs.

Is the DTC P0841 present also?

Yes

Refer to the Transmission category and perform the appropriate symptom.

Go To 2

2. CHECK THE DTC EVENT DATA FOR TRS CODE TR2

With the scan tool, check the DTC EVENT DATA for P1776.
Does the DTC EVENT DATA show a TRS Code of TR2?

Yes

This indicates the shift lever and the manual control valve were in an invalid position 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 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

Go To 3

3. CHECK TO SEE IF DTC P1776 IS CURRENT

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

Go To 9

4. CHECK THE PCM AND WIRING USING THE TRANSMISSION SIMULATOR

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

Go To 5

Go To 6

5. CHECK THE SOLENOID SWITCH VALVE FOR STICKING

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 per
the Service Information.

With the scan tool, record the DTC EVENT DATA for P1776 and erase DTCs.
Reassemble the transmission and test drive the vehicle. Try to duplicate the original set conditions using the DTC EVENT DATA recorded earlier.
With the scan tool, check Transmission DTCs.

Did the DTC P1776 reset?

Yes

Replace the Transmission Solenoid Assembly per the Service Information.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

Test Complete

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

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

Turn the ignition off to the lock position.
Disconnect the PCM C4 harness connector.
Disconnect the Transmission Solenoid/Pressure Switch Assembly 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
tool #8815 to perform diagnosis.
Measure the resistance of the (T50) L/R Pressure Switch Sense 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 Switch Sense circuit for an open.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

Go To 7

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

Measure the resistance between ground and the (T50) L/R Pressure Switch Sense circuit.

Is the resistance below 5.0 ohms?

Yes

Repair the (T50) L/R Pressure Switch Sense circuit for a short to ground.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

Go To 8

8. CHECK THE (T50) L/R PRESSURE SWITCH SENSE CIRCUIT FOR A SHORT TO VOLTAGE

Ignition on, engine not running.
With the scan tool under TIPM, actuate the Transmission.
Measure the voltage of the (T50) L/R Pressure Switch Sense circuit.

Is the voltage above 0.5 volts?

Yes

Repair the (T50) L/R Pressure Switch Sense circuit for a short to voltage.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

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 per the Service Information.
With the scan tool, perform QUICK LEARN.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

9. INTERMITTENT WIRING AND CONNECTORS

The conditions necessary to set this DTC are not present at this time.
Test drive the vehicle and verify if the transmission is launching in 2nd gear and/or there is no TCC engagement.
With the scan tool, check the EVENT DATA to help identify the conditions in which the DTC was set.
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 per the Service Information Inspect the Solenoid Switch Valve for sticking in its bore and repair or replace as necessary.

Perform 42RLE TRANSMISSION VERIFICATION TEST(Refer to 21 – TRANSMISSION/TRANSAXLE/AUTOMATIC – 42RLE – STANDARD PROCEDURE)

Test Complete.