Symptom:
P-0740 TORQUE CONV CLUTCH, NO RPM DROP AT LOCKUP
When Monitored and Set Condition:
P-0740 TORQUE CONV CLUTCH, NO RPM DROP AT LOCKUP
When Monitored: Continuously when no matured or maturing Trouble Code and throttle
position >10% and constant for 4.4 seconds before TCC engagement requested: No TCC
solenoid circuit, any cam/crank-related code, VSS, any TPS-related code and Battery
voltage >11.0
Set Condition: Torque Converter malfunctions that are detected are the FTC not locking
up properly when desired, and the torque converter not unlocking properly when desired.
3 consecutive test failures over one trip will store the code. 2 bad trips will set the code.
POSSIBLE CAUSES
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
DIFF, SHAFT, OR GEARS DEFECTIVE
TCC SOL DEFECTIVE
TORQUE CONVERTER ASSEMBLY DEF OR TCC SOL STUCK
TRANSMISSION FLUID DIRTY OR LEVEL LOW
VEHICLE CONFIGURATION NON-STANDARD
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, read codes.
Is the Global Good Trip displayed and equal to 0?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 2
No®Test Complete.
2 Ignition Off
At the9Cooler In9port puta0to300PSIgauge using a9T9. Ensure line is long
enough to reach in driver's side of vehicle so gauge can be monitored while driving.
Road test vehicle. Gear select in drive. While monitoring DRB, achieve 50 MPH.
While doing this, notice the gauge will read around 15 PSI until lockup is achieved
in 3rd gear. If the TCC Solenoid is operating properly, the gauge pressure will
fluctuate when lockup is achieved.
Did gauge fluctuate?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 3
No®Refer to service instructions for proper service procedure on
Torque Converter Assembly or stuck TCC Solenoid and repair as
necessary.
Perform Powertrain Verification Test VER-5A.
302
TRANSMISSION
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TEST ACTION APPLICABILITY
3 Ignition Off
Check Transmission Fluid level and ensure it is clear of any debris.
Is the Transmission Fluid okay?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 4
No®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
4 Ignition Off
Disconnect the TCC Solenoid connector.
Note: Check connectors - Clean/repair as necessary.
Turn key on.
Use a Voltmeter in the following step.
Using a Voltmeter, measure the Fused Ignition Switch Output Circuit at Solenoid
Connector.
Is the voltage above 10.0 volts?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 5
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-5A.
5 Ignition Off
Disconnect the TCC Solenoid connector.
Note: Check connectors - Clean/repair as necessary.
With an Ohmmeter, measure across the Solenoid for resistance.
Was resistance between 30.0 and 50.0 ohms?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 6
No®Replace TCC Solenoid.
Perform Powertrain Verification Test VER-5A.
6 Drive Vehicle
Maintain 50 MPH per DRB. Wait 10 seconds in lockup. Record Engine RPM.
Was engine RPM 2200 +/- 50 RPM?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Go To 7
No®Inspect Differential, Output Shaft, or Gear Box. Refer to service
instructions for proper diagnosis.
Perform Powertrain Verification Test VER-5A.
7 Ignition Off
Remove VSS.
Note: Check connectors - Clean/repair as necessary.
Inspect sensor and gear for damage, also improper wheel size.
Were any problems found?TRANSMISSION -
AUTOMATIC
3-SPD, 31TH
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-5A.
No®Test Complete.
303
TRANSMISSION
P-0740 TORQUE CONV CLUTCH, NO RPM DROP AT LOCKUP ÐContinued
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TEST ACTION APPLICABILITY
1 Using the DRB, erase the codes.
Turn ingition off.
Wait 10 seconds.
Turn ignition on.
Using the DRB, read the codes.
Does the DRB display the code that was previously erased?All
Ye s®Go To 2
No®Go To 4
2 Turn ignition off.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wire harness connectors. Look for broken,
bent, pushed out, or corroded terminals.
Note: Refer to any Technical Service Bulletins (TSB) that may apply.
Were any problems found?All
Ye s®Repair as necessary.
Perform the Powertrain Verification Test VER-7A.
No®Go To 3
3 Replace the Sentry Key Immobilizer Module.
Using the DRB, erase the codes.
Drive vehicle. Perform several key cycles.
Does the code appear?All
Ye s®Replace the Powertrain Control Module.
Perform the Powertrain Verification Test VER-7A.
No®Test Complete.
4 Turn ignition off.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wire harness connectors. Look for broken,
bent, pushed out, or corroded terminals.
Note: Refer to any Technical Service Bulletins (TSB) that may apply.
Were any problems found?All
Ye s®Repair wiring harness/connectors as necessary.
Perform the Powertrain Verification Test VER-7A.
No®Test Complete.
312
SENTRY KEY IMMOBILIZER SYSTEM
PCM STATUS FAILURE ÐContinued
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TEST ACTION APPLICABILITY
1 Using the DRB, erase the codes.
Turn ingition off.
Wait 10 seconds.
Turn ignition on.
Using the DRB, read the codes.
Does the DRB display the code that was previously erased?All
Ye s®Go To 2
No®Go To 4
2 Using the DRB, attempt to reprogram the ignition key to the SKIM Module.
Using the DRB, erase the codes.
Turn ignition off.
Wait 10 seconds.
Turn ignition on.
Using the DRB, read the codes.
Does the code appear?All
Ye s®Go To 3.
No®Test Complete.
3 Replace the ignition key with a new key.
Using the DRB, program the new ignition key to the SKIM Module.
Using the DRB, erase the codes.
Turn ignition off.
Wait 10 seconds.
Turn ignition on.
Using the DRB, read the codes.
Does the code appear?All
Ye s®Replace the Sentry Key Immobilizer Module.
Perform the Powertrain Verification Test VER-7A.
No®Test Complete.
4 Turn ignition off.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially borken wires.
Note: Visually inspect the related wire harness connectors. Look for broken,
bent, pushed out, or corroded terminals.
Note: Refer to any Technical Service Bulletins (TSB) that may apply.
Were any problems found?All
Ye s®Repair wiring harness/connectors as necessary.
Perform the Powertrain Verification Test VER-7A.
No®Test Complete.
314
TRANSPONDER (CYCLIC REDUNDANCY CHECK) CRC FAILURE Ð
Continued
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TEST ACTION APPLICABILITY
3 Turn ignition off.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wire harness connectors. Look for broken,
bent, pushed out, or corroded terminals.
Note: Refer to any Technical Service Bulletins (TSB) that may apply.
Were any problems found?All
Ye s®Repair wiring harness/connectors as necessary.
Perform the Powertrain Verification Test VER-7A.
No®Test Complete.
316
SENTRY KEY IMMOBILIZER SYSTEM
VIN MISMATCH ÐContinued
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Verification Tests
VERIFICATION TEST VER-1A APPLICABILITY
No Start Verification
Use this test to verify that a No Start condition has been repaired and that the vehicle can be
returned to the customer.
Note: If the Powertrain Control Module has been replaced and the correct VIN and
mileage have not been programmed, a DTC will be set in the ABS, Airbag and the
SKIM modules. In addition, if the vehicle is equipped with a Sentry Key Immobilizer
Module (SKIM), Secret Key data must be updated to enable starting. Refer to
GENERAL INFORMATION section for programming information for the PCM, SKIM
and the Transponder (ignition key).
1. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
2. Inspect the engine oil for fuel contamination. Replace the oil and filter as necessary
3. Attempt to start the engine.
4. If the No Start condition is still present, refer to the symptom list and perform diagnostic
testing as necessary. Refer to any Technical Service Bulletins that may apply.
5. Run the engine for one warm-up cycle to verify proper operation. With the DRBIIIt, confirm
that no DTC's are present and that all components are functioning properly.
6. If DTC's are present, refer to the symptom list and perform diagnostic testing as necessary.ALL
VERIFICATION TEST VER-2A APPLICABILITY
Non-OBDII Verification
Use this test to verify that a non-OBDII symptom has been repaired and that the vehicle can
be returned to the customer. A non-OBDII symptom is a comprehensive component related
symptom that is not the result of a failed OBDII major monitor.
Note: If the Powertrain Control Module has been replaced and the correct VIN and
mileage have not been programmed, a DTC will be set in the ABS, Airbag and the
SKIM modules. In addition, if the vehicle is equipped with a Sentry Key Immobilizer
Module (SKIM), Secret Key data must be updated to enable starting. Refer to
GENERAL INFORMATION section for programming information for the PCM, SKIM
and the Transponder (ignition key).
1. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
2. With the DRBIIIt, Clear DTC's and Reset Memory (all engine values).
3. Run the engine for one warm-up cycle to verify proper operation.
4. Road test the vehicle. Use all accessories that may be related to this repair.
With the DRBIIIt, confirm that no DTC's are present and that all components are functioning
properly.
6. If this test is being performed after a No Trouble Code test, verify that the symptom is no
longer present. If the symptom is still present, or any other symptom or DTC is present, refer
to the symptom list for further diagnostic testing procedures. Check for any Technical Service
Bulletins that may apply.
7. If there are no DTC's present and all components are functioning properly, repair is
complete.ALL
317
VERIFICATION TESTS
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VERIFICATION TEST VER-3A APPLICABILITY
Charging System Verification
Use this test to verify that the Charging System symptom has been repaired and that the
vehicle can be returned to the customer.
Note: If the Powertrain Control Module has been replaced and the correct VIN and
mileage have not been programmed, a DTC will be set in the ABS, Airbag and the
SKIM modules. In addition, if the vehicle is equipped with a Sentry Key Immobilizer
Module (SKIM), Secret Key data must be updated to enable starting. Refer to
GENERAL INFORMATION section for programming information for the PCM, SKIM
and the Transponder (ignition key).
1. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
2. With the DRBIIIt, Clear DTC's.
3. Perform generator output test. Refer to the appropriate service information as necessary.
4. Start the engine and set engine speed to 2000 RPM for at least thirty seconds.
5. Turn the ignition OFF.
6. Turn the ignition ON, with the engine not running.
7. With the DRBIIIt, Read the DTC's. If the DTC returns, or any other symptom or DTC is
present, refer to the symptom list for further diagnostic testing procedures. Check for any
Technical Service Bulletins that may apply.
8. If there are no DTC's present and all components are functioning properly, the repair is
complete.All
318
VERIFICATION TESTS
Verification Tests ÐContinued
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VERIFICATION TEST VER-4A APPLICABILITY
Speed Control Verification
Use this test to verify that the Speed Control symptom has been repaired and that the vehicle
can be returned to the customer.
Note: If the Powertrain Control Module has been replaced and the correct VIN and
mileage have not been programmed, a DTC will be set in the ABS, Airbag and the
SKIM modules. In addition, if the vehicle is equipped with a Sentry Key Immobilizer
Module (SKIM), Secret Key data must be updated to enable starting. Refer to
GENERAL INFORMATION section for programming information for the PCM, SKIM
and the Transponder (ignition key).
1. Inspect the vehicle to ensure that all components related to the repair are connected
properly.
2. With the DRBIIIt, Clear DTC's.
3. Road test the vehicle at a speed above 35 MPH.
4. Turn the Speed Control ON.
5. Press and release the Set switch. Verify that the speed control engages.
6. With the Speed Control engaged:
A. Press and hold the ACCEL switch. Verify that the speed increases.
B. Press and hold the SET (or DECEL) switch. Verify that the vehicle speed decreases.
C. Press and release the CANCEL switch. Verify that the Speed Control disengages.
D. Allow the vehicle speed to drop below 25 MPH. Press and release the RESUME switch.
Verify that the previously set vehicle speed is attained.
E. Using caution, press and release the brake pedal. Verify that the Speed Control
disengages.
F. Increase vehicle speed by at least 10 MPH. Press and release the SET switch. Verify the
Speed Control maintains this speed.
G. Press and release the ON/OFF switch (turn the Speed Control OFF.) Verify that the Speed
Control disengages.
If any or all of these functions are not operating properly, refer to the symptom list for the
appropriate diagnostic testing procedures.
7. With the DRBIIIt, Read DTC's. If the DTC returns, or any other symptom or DTC is present,
refer to the symptom list for further diagnostic testing procedures. Check for any Technical
Service Bulletins that may apply.
8. If there are no DTC's present and all components are functioning properly, the repair is
complete.All
319
VERIFICATION TESTS
Verification Tests ÐContinued
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