Page 2285 of 2305

Symptom:
TRANS TEMP SENSOR ERRATIC
When Monitored and Set Condition:
TRANS TEMP SENSOR ERRATIC
When Monitored: When transmission temperature is below 170É C (338É F)
Set Condition: When there is a 10É C (18É F) variation between each transmission
temperature sensor read. If the DTC is reset (after an ignition cycle), the DTC will be set
to Stored (Intermittent) status.
POSSIBLE CAUSES
TRANSMISSION TEMP SENSOR WIRING
TCM - TRANS TEMP SENSOR ERRATIC
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, monitor the Transmission Temperature.
With the brakes firmly applied, place the gear selector in Drive.
While monitoring the DRBIIIt, wiggle the wires and connectors from the TCM to the
Transmission Solenoid Assembly.
Did the Transmission Temperature fluctuate while wiggling the wires?All
Ye s!Repair the wiring and/or connectors as necessary.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 3
120
TRANSMISSION - NAG1
Page 2286 of 2305
TEST ACTION APPLICABILITY
3 Replace the Transmission Temp Sensor - P/N Switch Assembly per the Service
Information.
Perform W5J400 TRANSMISSION VERIFICATION TEST - VER 1.
Did the DTC, TRANS TEMP SENSOR ERRATIC, reset?All
Ye s!Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Test Complete.
121
TRANSMISSION - NAG1
TRANS TEMP SENSOR ERRATIC ÐContinued
Page 2287 of 2305

Symptom:
TRANS TEMP SENSOR SHORTED
When Monitored and Set Condition:
TRANS TEMP SENSOR SHORTED
When Monitored: Always monitored with system active
Set Condition: Temperature sensor input below a threshold, failed temperature sensor,
short to ground, TCM
POSSIBLE CAUSES
TEMP SENSOR - P/N SWITCH CIRCUIT SHORT TO GROUND
TEMP SENSOR - P/N SWITCH CIRCUIT SHORT TO OTHER CIRCUITS
TCM - P/N SWITCH CIRCUIT
TRANSMISSION TEMPERATURE SENSOR
TCM - TRANS TEMP SENSOR SHORTED
TRANSMISSION TEMP SENSOR - P/N 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 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 Attempt to start the vehicle in Park and Neutral.
Does the engine start in either position, Park or Neutral?All
Ye s!Go To 3
No!Go To 5
122
TRANSMISSION - NAG1
Page 2288 of 2305

TEST ACTION APPLICABILITY
3 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Place the gear selector to Drive (D).
Measure the resistance of the Transmission Temperature Sensor between the Temp
Sensor - P/N Switch circuit and the Sensor Ground circuit in the TCM C2 harness
connector.
Is the resistance between 500 ohms and 2500 ohms.All
Ye s!Go To 4
No!Check for a poor terminal to pin connections at the Solenoid
Assembly harness connector and repair as necessary. If no prob-
lems are found in the connector, replace the Transmission Tem-
perature Sensor - P/N Switch Assembly per the Service Informa-
tion.
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.
5 Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid harness connector.
NOTE: This procedure may set several DTCs in both the ECM and TCM.
Disregard and erase DTCs after this procedure.
With the gear selector in park, attempt to start the vehicle.
Does the vehicle start?All
Ye s!Replace the Transmission Temperature Sensor - P/N Switch
Assembly per the Service Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 6
6 Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Disconnect the Transmission Solenoid Assembly harness connector.
Measure the resistance between ground and the Temp Sensor - P/N Switch circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the Temp Sensor - P/N Switch circuit for a short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 7
7 Turn the ignition off to the lock position.
Disconnect the Transmission Solenoid Assembly harness connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the TCM C1 and C2 harness connectors.
Measure the resistance of the Temp Sensor - P/N Switch circuit to all other circuits
in the TCM C1 and C2 harness connectors.
Is the resistance below 5.0 ohms between any other circuit?All
Ye s!Repair the Temp Sensor - P/N Switch circuit for a short to other
circuits.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 8
123
TRANSMISSION - NAG1
TRANS TEMP SENSOR SHORTED ÐContinued
Page 2289 of 2305
TEST ACTION APPLICABILITY
8 If there are no possible causes remaining, view repair. All
Repair
Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
124
TRANSMISSION - NAG1
TRANS TEMP SENSOR SHORTED ÐContinued
Page 2290 of 2305

Symptom:
TRANSMISSION SLIPPING
When Monitored and Set Condition:
TRANSMISSION SLIPPING
When Monitored: Engine rpm greater than 450 rpm, output speed greater than 180 rpm,
no N2 - N3 input speed sensor errors present, no gear selector lever errors present, no ABS
system errors, no transfer case errors present, and all wheel speeds between 70 - 380 rpm
with no wheel slip detected. Set Condition: Calculated ratio not within allowable range for
the engaged gear. No shifting operation.
Set Condition: The TCM constantly calculates the transmission ratio based on the N2 -
N3 input speed signals and the calculated output shaft speed (CAN message from the
ABS). The TCM will detect if the transmission is slipping or an invalid gear ratio is present
POSSIBLE CAUSES
OTHER DTCS PRESENT
AXLE - MECHANICAL - GEAR RATIO
INTERNAL TRANSMISSION
TCM - TRANSMISSION SLIPPING
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
125
TRANSMISSION - NAG1
Page 2296 of 2305

9.0 CONNECTOR PINOUTS
ELECTROHYDRAULIC CONTROL UNIT - BLACKCAV CIRCUIT FUNCTION
1 20BL/DG N3 INPUT SPEED SENSOR
2 16BR/GY MODULATION PRESSURE SOLENOID CONTROL
3 20BL/GY N2 INPUT SPEED SENSOR
4 20GY/BL TEMPERATURE SENSOR-P/N SWITCH
5- -
6 16BK SOLENOID SUPPLY VOLTAGE
7 20BK/BL SENSOR SUPPLY VOLTAGE
8 16WT/BL 2-3 SOLENOID CONTROL
9 16YL 3-4 SOLENOID CONTROL
10 16BK/RD SHIFT PRESSURE SOLENOID CONTROL
11 16YL/BL TCC SOLENOID CONTROL
12 20PK SENSOR GROUND
13 16WT 1-2/4-5 SOLENOID CONTROL
SHIFTER ASSEMBLY - BLACKCAV CIRCUIT FUNCTION
1- -
2 20GY/DG/RD LAMP DRIVER
3 20BL/DG K-ABS/SHIFTER ASSEMBLY
4 18BR GROUND
5 20BK/BL/RD BRAKE LAMP SWITCH
6 20DG/WT CAN C BUS (+)
7 20DG CAN C BUS (-)
8 18BK/DG TRANSMISSION RELAY OUTPUT
9 16WT/BL/RD FUSED IGNITION SWITCH OUTPUT (RUN-START)
10 16WT/RD BACK-UP LAMP
TRANSMISSION CONTROL MODULE C1 - BLACKCAV CIRCUIT FUNCTION
1 20BL K-TCM/RADIO
2- -
3- -
4- -
5- -
6- -
7- -
8- -
9- -
10 - -
23 - -
24 - -
25 - -
26 - -
27 - -
28 - -
29 16BK/DG TRANSMISSION RELAY OUTPUT
30 18BR GROUND
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CONNECTOR PINOUTS
Page 2297 of 2305
TRANSMISSION CONTROL MODULE C2 - BLACKCAV CIRCUIT FUNCTION
12 20BL/GY N2 INPUT SPEED SENSOR
13 20BK/BL SENSOR SUPPLY VOLTAGE
14 16WT 1-2/4-5 SOLENOID CONTROL
15 16YL 3-4 SOLENOID CONTROL
16 16WT/BL 2-3 SOLENOID CONTROL
17 16YL/BL TCC SOLENOID CONTROL
33 20PK SENSOR GROUND
34 20GY/BL TEMPERATURE SENSOR-P/N SWITCH
35 20BL/DG N3 INPUT SPEED SENSOR
36 16BR/GY MODULATION PRESSURE SOLENOID CONTROL
37 16BK/RD SHIFT PRESSURE SOLENOID CONTROL
38 16BK SOLENOID SUPPLY VOLTAGE
H 20DG/WT CAN C BUS (+)
L 20DG CAN C BUS (-)
C
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132
CONNECTOR PINOUTS