TEST ACTION APPLICABILITY
6 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between the Shift Pressure Solenoid Control circuit and the
Solenoid Supply Voltage circuit in the Transmission Control Module C2 harness
connector.
Is the resistance between 4.0 and 8.0 ohms?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Shift Pressure Solenoid.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
7 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wires while checking for shorts and open circuits.
NOTE: Check for any Technical Service Bulletins that may apply.
Were there any problems found?All
Ye s!Repair as necessary
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test Complete.
101
TRANSMISSION - NAG1
SHIFT PRESSURE SOLENOID CIRCUIT ÐContinued
Symptom:
SLA CAN MESSAGE INCORRECT
POSSIBLE CAUSES
SHIFT LEVER ASSEMBLY DTCS PRESENT
PCM/ECM - ENGINE TORQUE MESSAGE INCORRECT
TCM - TORQUE MESSAGE INCORRECT
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 DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs 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 controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any performance or bus related Engine DTCs present?All
Ye s!Refer to the Shift Lever category and perform the appropriate
symptom.
No!Go To 3
3 Replace and program the ECM per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Drive the vehicle performing multiple aggressive upshifts and downshifts.
With the DRBIIIt, read Transmission DTCs.
Did the DTC, ENGINE TORQUE MESSAGE INCORRECT, reset?All
Ye s!Go To 4
No!Test Complete
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
4 If there are no possible causes remaining, view repair. All
Repair
Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
102
TRANSMISSION - NAG1
Symptom:
SOLENOID SUPPLY VOLTAGE
When Monitored and Set Condition:
SOLENOID SUPPLY VOLTAGE
When Monitored: When the solenoid is active or not active and no under-voltage
condition exists.
Set Condition: If voltage is present when the output is off or the measured supply voltage
and measured battery voltage differ by 3.6 volts.
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
SOLENOID SUPPLY CIRCUIT SHORT TO OTHER CIRCUIT
SOLENOID SUPPLY VOLTAGE CIRCUIT SHORT TO GROUND
SOLENOID ASSEMBLY
TCM - SOLENOID SUPPLY VOLTAGE 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 DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs 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 controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 Ignition on, engine not running.
With the DRBIIIt, read Transmission DTCs.
Is the DTC, Solenoid Supply Voltage, displayed as ACTIVE?All
Ye s!Go To 3
No!Go To 6
103
TRANSMISSION - NAG1
TEST ACTION APPLICABILITY
3 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Solenoid Supply circuit to all other circuits in the
Transmission Solenoid harness connector.
Is the resistance below 5.0 ohms between any other circuit?All
Ye s!Repair the Solenoid Supply circuit for a short to other circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Solenoid Supply circuit to chassis ground in the
Transmission Solenoid harness connector.
Is the resistance below 5.0 ohms?All
Ye s!Repair the Solenoid Supply Voltage circuit for a short to ground or
high resistance.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 5
5 Turn the ignition off to the lock position.
Disconnect the Transmission Control Module C2 harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between all Solenoid Control circuits and chassis ground in
the Transmission Control Module C2 harness connector.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Solenoid that is shorted to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
6 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wires while checking for shorts and open circuits.
NOTE: Check for any Technical Service Bulletins that may apply.
Were there any problems found?All
Ye s!Repair as necessary
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test Complete.
104
TRANSMISSION - NAG1
SOLENOID SUPPLY VOLTAGE ÐContinued
Symptom:
SOLENOID SUPPLY/WATCHDOG
When Monitored and Set Condition:
SOLENOID SUPPLY/WATCHDOG
When Monitored: Always monitored with system active at each ignition cycle.
Set Condition: During the power up of the TCM, it tests the ability of the external
watchdog to shut down the Solenoid Supply driver.
POSSIBLE CAUSES
SOLENOID SUPPLY CIRCUIT SHORT TO OTHER CIRCUITS
SOLENOID DTCS PRESENT
TCM - SOLENOID SUPPLY WATCHDOG
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 DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs 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 controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 With the DRBIIIt, read DTCs..
Are any Solenoid DTCs present?All
Ye s!Repair all Solenoid DTCs before proceeding with test.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
105
TRANSMISSION - NAG1
TEST ACTION APPLICABILITY
3 Turn the ignition off to the lock position.
Remove the TCM harness connector.
Disconnect the Solenoid harness connector.
Check the resistance between the Solenoid Supply circuit and all other circuits in the
TCM harness connector.
Is the resistance below 5.0 ohms between Solenoid Supply and any other circuit?All
Ye s!Repair the Solenoid Supply circuit short to other circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!The TCM has an internal error. Replace the Transmission Control
Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
106
TRANSMISSION - NAG1
SOLENOID SUPPLY/WATCHDOG ÐContinued
Symptom:
SYSTEM OVERVOLTAGE
When Monitored and Set Condition:
SYSTEM OVERVOLTAGE
When Monitored: Always monitored with system active at each ignition cycle
Set Condition: Ignition voltage above 16.9 volts with the engine and transmission input
speed sensors above 2000 rpm for 60 seconds
POSSIBLE CAUSES
VEHICLE JUMP STARTED IMPROPERLY
ENGINE CHARGING SYSTEM DTC'S PRESENT
TRANSMISSION RELAY OUTPUT HIGH AT TCM
TCM - SYSTEM OVERVOLTAGE
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 DTCs. Check and repair all engine DTCs prior to
performing transmission symptom diagnostics.
With the DRBIIIt, read and record all Transmission DTCs.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal
connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
Repair as necessary.
Most DTCs 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 controller. Some problems are
corrected by software upgrades to the transmission controller.
NOTE: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.All
Continue
Go To 2
2 Determine is the vehicle was jump started improperly.
NOTE: If the battery was jump started with the batteries in series, the
System Overvoltage DTC will be set.
Was the vehicle jump started improperly?All
Ye s!Erase the DTC , if the vehicle was jump started improperly.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
107
TRANSMISSION - NAG1
TEST ACTION APPLICABILITY
3 With the DRBIIIt, read the Engine DTC's.
Are there any Engine Charging System DTC's present?All
Ye s!Refer to the Charging category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 4
4 Turn the ignition off to the lock position.
Disconnect the TCM C1 harness connector.
Check connectors - Clean/repair as necessary.
Start the engine.
Increase the Engine Speed to 1500 RPM.
Measure the voltage of the Transmission Relay Output circuit in the TCM C1
harness connector.
Is the voltage below 16.9 volts?All
Ye s!Go To 5
No!Refer the Charging category and perform the symptom, Charging
System with No DTCs present.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
5 If there are no possible causes remaining, view repair. All
Repair
Replace the TCM.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
108
TRANSMISSION - NAG1
SYSTEM OVERVOLTAGE ÐContinued