Symptom:
P1776-SOLENOID SWITCH VALVE LATCHED IN LR POSITION
When Monitored and Set Condition:
P1776-SOLENOID SWITCH VALVE LATCHED IN LR POSITION
When Monitored: Continuously when doing partial or full EMCC (PEMCC or FEMCC).
Set Condition: This DTC will set if the TCM senses the L/R Pressure Switch closing while
performing PEMCC or FEMCC or after two unsuccessful attempts to perform PEMCC or
FEMCC.
POSSIBLE CAUSES
INCORRECT FLUID LEVEL
RELATED DTC P1784 PRESENT
INTERMITTENT OPERATION
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
L/R PRESSURE SWITCH SENSE CIRCUIT OPEN
L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
INTERNAL TRANSMISSION - SOLENOID SWITCH VALVE STUCK
TCM - SOLENOID SWITCH VALVE
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
100
TRANSMISSION
TEST ACTION APPLICABILITY
2 With the DRBIIIt, check for other Transmission DTCs
Is the DTC P1784 present also?All
Ye s®Refer to symptom list and perform test for DTC P1784.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 3
3 Perform a visual inspection of all connectors, wiring, and cooler connections before
proceeding. Repair as necessary.
With the DRBIIIt, Check the STARTS SINCE SET counter.
NOTE: This counter only applies to the last DTC set.
Is the STARTS SINCE SET counter 2 or less?All
Ye s®Go To 4
No®Go To 12
4 Turn the ignition off to the lock position.
CAUTION: Remove the Starter Relay from the IPM. This will prevent the
vehicle from being started in gear.
Install Transmission Simulator, Miller tool #8333 and the FWD Adapter Cable kit,
Miller tool #8333-1.
Ignition on, engine not running.
On the Transmission Simulator select L/R on the Pressure Switch selector switch.
With the DRBIIIt, monitor the L/R Pressure Switch state while pressing the
Pressure Switch Test button on the Transmission Simulator.
Did the Pressure Switch state change from OPEN to CLOSED when the test button
was pressed?All
Ye s®Go To 5
No®Go To 7
5 Check the Transmission Fluid Level per the Service Information.
Is the Transmission Fluid Level at the proper level?All
Ye s®Go To 6
No®If the Transmission Fluid is low, repair any Transmission Fluid
leak as necessary and adjust the Transmission Fluid Level in
accordance with the Service Information.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
6 If there are no possible causes remaining, view repair. All
Repair
Inspect the Solenoid Switch Valve in the valve body per the
Service Information and repair or replace as necessary. If no
problems are found in valve body, replace the Transmission
Solenoid/Pressure Switch Assembly per service information.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
101
TRANSMISSION
P1776-SOLENOID SWITCH VALVE LATCHED IN LR POSITION Ð
Continued
Symptom:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored and Set Condition:
P1781-OD PRESSURE SWITCH SENSE CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: The appropriate DTC is set if one of the Pressure Switches are open or
closed at the wrong time in a given gear.
POSSIBLE CAUSES
TRANSMISSION RELAY DTCS PRESENT
INTERMITTENT WIRING AND CONNECTORS
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
O/D PRESSURE SWITCH SENSE CIRCUIT OPEN
O/D PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
O/D PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
O/D PRESSURE SWITCH INOPERATIVE
TCM - O/D PRESSURE SWITCH
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
104
TRANSMISSION
Symptom:
P1782 - 2-4 PRESSURE SWITCH SENSE CIRCUIT
When Monitored and Set Condition:
P1782 - 2-4 PRESSURE SWITCH SENSE CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: The appropriate DTC is set if one of the Pressure Switches are open or
closed at the wrong time in a given gear .
POSSIBLE CAUSES
TRANSMISSION RELAY DTC'S PRESENT
INTERMITTENT WIRING AND CONNECTORS
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
2/4 PRESSURE SWITCH SENSE CIRCUIT OPEN
2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
2/4 PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
2/4 PRESSURE SWITCH
TCM - 2/4 PRESSURE SWITCH CIRCUIT
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
107
TRANSMISSION
Symptom:
P1784-LR PRESSURE SWITCH SENSE CIRCUIT
When Monitored and Set Condition:
P1784-LR PRESSURE SWITCH SENSE CIRCUIT
When Monitored: Whenever the engine is running.
Set Condition: The appropriate DTC is set if one of the Pressure Switches are open or
closed at the wrong time in a given gear .
POSSIBLE CAUSES
LOSS OF PRIME DTC P1791 PRESENT
TRANSMISSION CONTROL RELAY DTCS PRESENT
TCM AND WIRING - L/R PRESSURE SWITCH
INTERMITTENT WIRING AND CONNECTORS
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
L/R PRESSURE SWITCH SENSE CIRCUIT OPEN
L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO GROUND
L/R PRESSURE SWITCH SENSE CIRCUIT SHORT TO VOLTAGE
TCM - L/R PRESSURE SWITCH CIRCUIT
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
11 0
TRANSMISSION
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 With the DRBIIIt, check for other Transmission DTCs.
Is the DTC P1791 present also?All
Ye s®Refer to symptom list and perform test for P1791.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 3
3 With the DRBIIIt, read Transmission DTC's.
Is the DTC P0733 and/or P1781 present also?All
Ye s®Replace the Transmission or Solenoid/Pressure Switch Assembly.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 4
4 With the DRBIIIt, Check the STARTS SINCE SET counter.
NOTE: This counter only applies to the last DTC set.
Is the STARTS SINCE SET counter 2 or less?All
Ye s®Go To 5
No®Go To 13
11 5
TRANSMISSION
P1787-OD HYDRAULIC PRESSURE TEST FAILURE ÐContinued
TEST ACTION APPLICABILITY
5 Turn the ignition off to the lock position.
CAUTION: Remove the Starter Relay from the IPM. This will prevent the
vehicle from being started in gear.
Install Transmission Simulator, Miller tool #8333 and the FWD Adapter Cable kit,
Miller tool #8333-1.
Note: Check connectors - Clean/repair as necessary.
On the Transmission Simulator select OD on the Pressure Switch selector switch.
With the DRBIIIt, monitor the OD Pressure Switch state while pressing the
Pressure Switch Test button on the Transmission Simulator.
Wiggle the wires leading to the TCM while pressing the button.
Did the O/D Pressure Switch state change to closed and remain closed while wiggling
the wires?All
Ye s®Go To 6
No®Go To 8
6 The Transmission must be above 21É C or 70É F prior to checking fluid level.
Adjusting fluid level on a cold transmission will result in an overfilled transmission.
Check the Transmission Fluid Level per the Service Information.
Is the fluid level OK?All
Ye s®Go To 7
No®Adjust fluid level. Repair cause of incorrect fluid level.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
7 If there are no possible causes remaining, view repair. All
Repair
Disassemble and inspect the Valve Body per service instructions
and repair or replace as necessary. If no problems are found in the
valve body, replace the Transmission Solenoid Pressure Switch
Assembly per the Service Information.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
8 Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid/Pressure Switch harness connector.
Remove the Transmission Control Relay from the IPM
Note: Check connectors - Clean/repair as necessary.
Connect a jumper wire between the Fused B+ circuit and the Transmission Control
Relay Output circuit in the Transmission Control Relay connector in the IPM.
Using a 12-volt test light connected to ground, check the Transmission Control Relay
Output circuit in the Solenoid/Pressure Switch Assembly harness connector.
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?All
Ye s®Go To 9
No®Repair the Transmission Control Relay Output circuit for an open
or high resistance. If the fuse is open make sure to check for a
short to ground.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
11 6
TRANSMISSION
P1787-OD HYDRAULIC PRESSURE TEST FAILURE ÐContinued
TEST ACTION APPLICABILITY
1NOTE: Low fluid level can be the cause of many Transmission problems. If
the fluid level is low locate and repair the leak then check and adjust the
fluid level per the Service Information.
NOTE: Always perform diagnostics with a fully charged battery to avoid
false symptoms.
With the DRBIIIt, read the engine DTC's. Check and repair all engine DTC's prior
to performing Transmission Symptom Diagnostics.
With the DRBIIIt, read Transmission DTC's. Record all DTC's and 1 Trip Failures.
NOTE: Diagnose 1 Trip Failures as a fully matured DTC.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Perform the Shift Lever Position Test. If the test does not pass, refer to Symptom test
for P0705 Check Shifter Signal.
For Gear Ratio DTC's, check and record all CVI's.
Most DTC's set on start up but some must be set by driving the vehicle such that all
diagnostic monitors have run.
NOTE: Verify flash level of Transmission Control Module. Some problems
are corrected by software upgrades to the Transmission Control Module.
NOTE: Check for applicable TSB's related to the symptom.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 With the DRBIIIt, check for other Transmission DTCs.
Is the DTC P1791 present also?All
Ye s®Refer to symptom list and perform test for P1791.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 3
3 With the DRBIIIt, read Transmission DTC's.
Is the DTC P0732, P0734 and/or P1782 present also?All
Ye s®Replace the Transmission or Solenoid/Pressure switch assembly.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 4
4 With the DRBIIIt, Check the STARTS SINCE SET counter.
NOTE: This counter only applies to the last DTC set.
Is the STARTS SINCE SET counter 2 or less?All
Ye s®Go To 5
No®Go To 13
11 9
TRANSMISSION
P1788-2/4 HYDRAULIC PRESSURE TEST FAILURE ÐContinued