Page 2205 of 2305

Symptom:
ABS LR SENSOR MESSAGE
When Monitored and Set Condition:
ABS LR SENSOR MESSAGE
When Monitored: Valid ABS CAN messages received at least once and the CAN Bus
circuit, ABS CAN Message Missing, ABS CAN Message Incorrect are not active
Set Condition: ABS signal9wheel speed rear left9not valid or ABS has detected a sensor
failure.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
ABS DTCS PRESENT
ABS CONTROL MODULE - ABS LR SENSOR MESSAGE
TCM - ABS LR SENSOR MESSAGE
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.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
40
TRANSMISSION - NAG1
Page 2206 of 2305
TEST ACTION APPLICABILITY
3 Ignition on, engine not running.
With the DRBIIIt, read ABS DTCs.
Are there any ABS DTCs present?All
Ye s!Refer to the BRAKE 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.
Replace the ABS Control Module per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Road test the Vehicle.
With the DRBIIIt, read Transmission DTCs.
Does the DTC, ABS LR SENSOR MESSAGE, reset?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test complete.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
41
TRANSMISSION - NAG1
ABS LR SENSOR MESSAGE ÐContinued
Page 2207 of 2305

Symptom:
ABS RF SENSOR MESSAGE
When Monitored and Set Condition:
ABS RF SENSOR MESSAGE
When Monitored: Valid ABS CAN messages received at least once and the CAN Bus
circuit, ABS CAN Message Missing, ABS CAN Message Incorrect are not active
Set Condition: ABS signal9Wheel Speed Front Right9not valid or ABS has detected a
sensor failure.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
ABS DTCS PRESENT
ABS CONTROL MODULE - ABS RF SENSOR MESSAGE
TCM - ABS RF SENSOR MESSAGE
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.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
42
TRANSMISSION - NAG1
Page 2208 of 2305
TEST ACTION APPLICABILITY
3 Ignition on, engine not running.
With the DRBIIIt, read ABS DTCs.
Are there any ABS DTCs present?All
Ye s!Refer to the BRAKE 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.
Replace the ABS Control Module per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Road test the Vehicle.
With the DRBIIIt, read Transmission DTCs.
Does the DTC, ABS RF SENSOR MESSAGE, reset?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test complete.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
43
TRANSMISSION - NAG1
ABS RF SENSOR MESSAGE ÐContinued
Page 2209 of 2305

Symptom:
ABS RR SENSOR MESSAGE
When Monitored and Set Condition:
ABS RR SENSOR MESSAGE
When Monitored: Valid ABS CAN messages received at least once and the CAN Bus
circuit, ABS CAN Message Missing, ABS CAN Message Incorrect are not active
Set Condition: ABS signal9wheel speed rear right9not valid or ABS has detected a sensor
failure.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
ABS DTCS PRESENT
ABS CONTROL MODULE - ABS RR SENSOR MESSAGE
TCM - ABS RR SENSOR MESSAGE
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.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
44
TRANSMISSION - NAG1
Page 2210 of 2305
TEST ACTION APPLICABILITY
3 Ignition on, engine not running.
With the DRBIIIt, read ABS DTCs.
Are there any ABS DTCs present?All
Ye s!Refer to the BRAKE 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.
Replace the ABS Control Module per the Service Information.
With the DRBIIIt, erase Transmission DTCs.
Road test the Vehicle.
With the DRBIIIt, read Transmission DTCs.
Does the DTC, ABS RR SENSOR MESSAGE, reset?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test complete.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
45
TRANSMISSION - NAG1
ABS RR SENSOR MESSAGE ÐContinued
Page 2211 of 2305

Symptom:
ACCEL PEDAL SENSOR CAN MESSAGE INCORRECT
When Monitored and Set Condition:
ACCEL PEDAL SENSOR CAN MESSAGE INCORRECT
When Monitored: When a valid Accelerator Pedal Position (APP) CAN Message Received
at least once and the DTCs, CAN Bus Circuit, Engine CAN Message Missing and Engine
CAN Message Incorrect are not active.
Set Condition: Accelerator Pedal Position (APP) Message not valid or a ECM Engine
Sensor DTC detected.
POSSIBLE CAUSES
CAN BUS CIRCUIT DTC PRESENT
ENGINE ACCEL PEDAL DTCS PRESENT
ENGINE COMMUNICATION DTCS PRESENT
INTERMITTENT WIRING AND CONNECTORS
ECM - ACCEL PEDAL SENSOR CAN 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
46
TRANSMISSION - NAG1
Page 2212 of 2305

TEST ACTION APPLICABILITY
2 With the DRBIIIt, read Transmission DTCs.
NOTE: If the DTC, CAN BUS CIRCUIT, is present, perform diagnostics on
that symptom first.
Is the DTC, CAN BUS CIRCUIT, present?All
Ye s!Refer to the Transmission category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
3 With the DRBIIIt, read Transmission DTCs.
Is the DTC Accel Pedal Sensor CAN Message Incorrect displayed as ACTIVE?All
Ye s!Go To 4
No!Go To 8
4 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any Engine bus related DTCs present?All
Ye s!Refer to the Communication category and perform the appropri-
ate symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 5
5 Ignition on, engine not running.
With the DRBIIIt, read Engine DTCs.
Are there any Accel Pedal DTCs present?All
Ye s!Refer to the Driveability category and perform the appropriate
symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 6
6 Replace the Transmission Control Module.
NOTE: Perform the transmission verification test.
Did the DTC9Accel Pedal Sensor CAN Message Incorrect9reset?All
Ye s!Go To 7
No!Test Complete.
7 If there are no possible causes remaining, view repair. All
Repair
Replace the Engine Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
8 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.
47
TRANSMISSION - NAG1
ACCEL PEDAL SENSOR CAN MESSAGE INCORRECT ÐContinued